Guilford Journal of Chemistry 2011-1012 by ChemistryAdventure

Table of Contents Period 2 Jacob H, Ben B, Colton S The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Craig A The Effect Various Mentos Has on Diet Coke Courtney O The Colder the Temperature of Coke the Higher a Mentos Eruption Anny Y Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anna K Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Ambur D Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Period 3 Catherine D The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Claire W and Lindsey U Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Shane G and Clara P How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Jenna P The height of the Mentos eruption depends on the outside coating Marguerite D and Alex P Diet Coke vs. Energy Drinks Period 4 Sara D and Alexa B Crushing Mentos will not make the eruption larger Andrew T and Mark L Mentos Car Eruption Michael G Diet Pepsi and Mentos: Elongated Eruptions

Period 5 Ben E Drilling holes in the Mentos will increase eruption height Dan F and Samuel W The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction

Evan H and Michel I Smaller Nozzle Size Creates Larger Spray during the Mentos Eruptions Grace I and Amanda M High Surface Area Increases a Coke Mentos Eruption Height Olivia S and Bronwyn R The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Ashely Z and Katie N Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mento Period 7 Jack F and Jamie W The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Kate C., Anny Y., Annie X. Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Rebecca E and Klaire C Mentos, Baking Soda, and Vinegarâ&#x20AC;Ś.A Quench to an Eruptionâ&#x20AC;&#x2122;s Thirst Zoe B and Nicole B Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda

The Effect of Different Sodas on the Height of a Soda and Mentos Eruption Jacob H, Ben B, Colton S

Summary For our experiment, we decided to test eight different types of soda to see how high their respective Mentos-induced eruptions would be, if any eruptions would even occur at all. The sodas that we used were Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero. We expected Diet Coke to produce the highest spray at 533.5 cm simply because this soda is the one most famously used in this experiment. However, Coke Zero surpassed the Diet Coke by 27.5 cm, achieving an astonishing height of 561 cm. In order from the highest spray to the lowest spray; Coke Zero (561 cm), Diet Coke (533.5 cm), Diet Pepsi (473 cm), Coca-Cola (434.5 cm), Sprite (363 cm), and Grape Soda (247.5 cm). Our two remaining drinks, the Seltzer and Pepsi Max, are unable to be compared to the other drinks because both tests involving these drinks failed. The Seltzer fell over mid-eruption and the Mentos became lodged in the geyser tube for the Pepsi Max. Introduction The Mentos Eruption Experiment has become a worldwide phenomenon ever since the first videos of this experiment started showing up on YouTube. Then, in 2006 the Discovery Channel show “Mythbusters” tackled the experiment themselves. Despite all of the publicity and attention this simple experiment has achieved, only one scientific paper has been written, reviewed, and published to the scientific community. In this paper, Tonya Coffey conducts the Diet Coke and Mentos experiment using a variety of sodas and potential reagents. At the end of her paper, Coffey concludes that potassium benzoate and aspartame are two main reagents that cause the eruption. She also concluded that the surface roughness of the reagents and the temperature of the sodas are major components in the reaction as well. 1 Experimental Section Materials: 2 liter bottles of Diet Pepsi, Seltzer, Grape Soda, Diet Coke, Sprite, Coca-Cola, Pepsi Max, and Coke Zero at room temperature; 72 individual Mentos; a geyser tube; a damp rag for cleaning 1. Load 9 Mentos into the geyser tube and sure the pin and slider. Make sure the components won’t accidentally slip. 2. Unscrew the top of a soda bottle and quickly place the geyser tube into the bottle. Secure the tube to the bottle. 3. Place the bottle next to a wall or some device capable of measuring the height of the eruption. Angle the bottle approximately 80 degrees, pointing toward the wall. 4. Hold the bottle tightly to prevent it from falling over and pull the pin out of the geyser tube in a smooth, quick motion. Continue to hold the bottle throughout the eruption to prevent it from tipping. 5. Measure the height of the soda on the wall and record your data. 6. Use the damp rag to clean out the tube after the eruption to prevent the new Mentos from sticking to the inside of the tube. 7. Repeat steps 1 through 6 using each individual soda for as many trials as desired. Results Diet Grape Diet Sprite CocaCoke Pepsi Soda Coke Cola Zero Height of 473 cm 247.5 cm 533.5 cm 363 cm 434.5 cm 102 cm Eruption

Height of Mentos Eruptions with Different Sodas 600 500 400 Height of Eruption 300 (cm) 200 100 0 Diet Pepsi

Grape Soda

Diet Coke

Sprite

Coca-Cola

Coke Zero

Types of Soda

Conclusion After conducting the experiment, we found that Coke Zero achieved the highest eruption. As for a scientific explanation for this result, we cannot provide one. The ingredients in Coke Zero are very similar to the ingredients in Diet Coke; they both contain aspartame and sodium benzoate, which Coffey found to be the major reagents in this reaction so as to why the Coke Zero achieved a higher eruption is unknown. It is also impossible to determine whether the data associated with any of these sodas is consistent because only one trial was conducted with each type of soda, so these results could have just been a random occurrence based on any number of factors. However, given the potentially flawed data as they are, general assumptions can be made. It appears that since the diet drinks (Coke Zero, Diet Coke, and Diet Pepsi) had the top three highest eruptions, something must be present in these three drinks that causes them to be particularly volatile when exposed to Mentos as opposed to the other drinks which still reacted to the mints, but not nearly as explosively. In addition to the potential for the data above to be flawed, it should also be noted that two other drinks, Seltzer and Pepsi Max were tested. However, these drinks were not included in the results because both tests malfunctioned and a reliable height measurement could not be obtained so it would be inappropriate to attempt to compare these two errors to the above data. A relevant follow-up experiment to ours could be conducted using the same sodas, however more trials for each soda should be performed in order to reveal if our data truly was flawed or semi-random; also additional trials would eliminate the need to exclude data because of failed trials such as ours. Endnotes Tonya Shea Coffey. â&#x20AC;&#x153;Diet Coke and Mentos: What is really behind this physical reaction?â&#x20AC;? 2008 Angelise Musterer and Lindsay Ruotolo. The Guilford Journal of Chemistry. Volume 2, pages 12-13 (2009). Another paper discussing a very similar experiment to ours in which they changed the types soda as well. 1

The Effect Various Mentos Has on Diet Coke: Craig A

The mentos and coke experiment has become a wide known result. You drop a few mentos into diet coke and out comes a geyser of coke spraying out the top. But this experiment took the mentos and used different types of mentos to test the variable height of each type. In this experiment there was mint and fruit mentos present. The mint sprayed, at best, 54 bricks high (or 108 inches because one brick is two inches tall). The fruit sprayed, at best, 81 bricks high (or 162 inches high). So this proves that the fruit creates a more powerful geyser than the mint. Also in the experiment performed by the college student, Coffey, she had the fruit mentos producing an explosion of a greater distance than the mint mentos.1 They had stating that the fruit mentos burst 17.8 feet, while the mint mentos went 16.3 feet.2 In the experiment performed by Tonya Shea Coffey, she had mint mentos exploding a shorter distance than the fruit mentos.3 The mentos and diet coke experiment that was performed in this experiment produced results showing that different mentos do, in fact, produce different geyser heights. If different mentos produced different outcomes then different mentos must have different make-ups because they would produce the same outcome if they were the same in their make-up. With the background research in mind the mentos experiment was predicted to be only slight differences between the different mentos. Because the mentos have numerous tiny pores in the surface layer of the candy the coke, in reaction, releases carbon dioxide at a very rapid rate. This is what causes the geyser of soda to erupt.4 What also ignites the geyser is the gelatin and gum arabic inside the mentos. The gum arabic and the gelatin cause the foam to form in the soda.5 In our experiment the fruit mentos went higher than the mint mentos proving that there is a difference in the two mentos. That difference caused as much as a 50 inch difference in height, in the explosion. Materials: 2 pairs of safety goggles 4 bottles of 2 litter diet coke 2 rolls of mentos: o Fruit o Mint 2 geyser tubes (didn’t know what to call them) Safety:  Be sure to wear your safety goggle at all time when handling the products.  Be sure clear a good distance before during and after the explosion.  Be sure to make the dropping of the mentos to be fluid and quick/make sure they won’t get stuck and not fall in, but fall in later.  Be sure to not drink the soda or eat the mentos after the experiment. 1

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Coffey’s results show that the mint

mentos are less powerful than the fruit in the explosion. 2

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ those numbers are from the packet

given to us by you. 3

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ it was 2.5 feet of a difference.

Wikipedia: Mentos and Diet Coke ~ CO2 was released due to these pores. I found this fact on Wikipedia.

Wikipedia: Mentos and Diet Coke ~ I found that these were ingredients in the mentos on Wikipedia.

Procedure: 1) Place safety goggles on your face. 2) Set your mentos into the tube, ready for the drop. 3) Place tube onto the diet coke. 4) Set up the coke so it is tilting just slightly towards the building, ready to move on to pull the string. 5) Pull the string and run a little away from the explosion to avoid the explosion. 6) Record observations. 7) Repeat the steps 2-5 for continuing trials and variables Heights: Trial 1: Trial 2: Fruit: 81 bricks 20 bricks: 202.5 inches 50 inches  There was a loose geyser tube and it exploded. Mint: 54 bricks 47 bricks 135 inches 117.5 inches

250

200

150 Trial 1 Trial 2

100

0 Fruit

Mint

This table shows that the experiment proved our hypothesis. The fact that there was such a difference in the heights shows that there is a different make-up between the two. A 202.5 inch height to a 135 inch difference is a significant difference when discussing the height. But when discussing the amounts lost, such as in Coffey’s experiment, there was 1440g lost from fruit mentos, and 1410g lost from the mint mentos.6 These results signify our successful completion of proving our hypothesis. The graphs and tables in Coffey’s lab prove and support our prediction as to how the mentos will affect the coke. They have small and 6

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ That is only 30g which is a really small

amount.

large differences in the mint and fruit conclusions.7 The experiment performed in this class has proof only with height. So the data is could have been expanded in so many ways, such as we could have had a third trial, or we could have had another kind of mentos. We could have also done left over in the can comparisons, eruption power comparisons, or types of soda. The geyser tube blew off so that changed our results and we got less reportable results. The table and graph are not as correct as they would have been had there not have been a mistake in the experiment.

Diet Coke and Mentos: What is really behind this physical reaction? By Tonya Shea Coffey ~ Some data concludes that the fruit is

much more powerful, but in other cases the fruit is less of an outlier from the mint.

The Colder the Temperature of Coke the Higher a Mentos Eruption Courtney O

Our group tested the effect of temperature on the height of a Mentos eruption. We wanted to see if the coldness of the coke would make the eruption higher. We discovered that the colder the coke the higher the eruption was. When our coke was room temperature or 71 degrees Fahrenheit it erupted to an average of 30 bricks. When our coke was chilled at a temperature of 46 degrees Fahrenheit it erupted to an average of 33 bricks. When our sample was cooled down to 37 degrees Fahrenheit it erupted to an average of 34.5 bricks. This shows that cold soda does cause for a higher eruption but the difference between the chilled and cold soda is not very much. The percentage increase from room temperature to 46 degrees is 9%. Meanwhile the percentage increase from 46 degrees to 37 degrees is only 4%. This shows us that once the soda is cold it doesn’t have as much as an effect because the difference between the chilled and cold soda is not nearly as big a percentage between the room temperature and the chilled coke. The coke and Mentos experiment occurs when Mentos are dropped in a fresh bottle of coke and results in an eruption from the coke bottle. Depending on many different factors the height of the eruption can greatly vary. An experiment involving temperature was conducted by Cutler and Smith who showed that the height of the eruption could be dramatically increased by the freezing of the Mentos candies. This is similar to the experiment we conducted because it involves the coldness of the materials used. They also found similar results to ours showing that the coldness makes the eruption higher but after a certain point it doesn’t make as great of a difference. In the article written by Tonya Shea Coffey about what is really behind the physical reaction involved in a Mentos eruption he talks about how varying temperatures of soda cause the mass to vary which may show why an eruption is higher when the soda is colder. The lack of mass in the colder sodas could show the reason why we got the results we did, with the colder bottles of coke creating the highest eruption. When conducting a coke and Mentos experiment to see how temperature affects the height of the eruption you need to have a total of forty-five Mentos and nine bottles of soda to carry out the experiment accurately. You will also need a geyser tube and a way of measuring how high your eruption goes, such as a wall. The first thing you need to do is put six bottles of soda into the refrigerator waiting for three of these bottles to reach a temperature of 8 degrees Celsius and the remaining three to reach a temperature for 3 degrees Celsius. The three bottles you kept out of the refrigerator will be your control or room temperature samples and should be around 22 degrees Celsius. Once you have all your sodas at the proper temperature you put five Mentos into a geyser tube, line your soda up against your wall and drop the Mentos into a freshly opened bottle of soda. Repeat this for all nine bottles, so that you do each temperature three times. Find the average of this data and you will see if how cold the soda is affects the height of a Mentos eruption. Temperature ⁰C 22⁰C 8⁰C 3⁰C

Trial #1 32 bricks 33 bricks 32.5 bricks

Trial #2 28 bricks 35 bricks 36 bricks

Trial #3 31 bricks 31 bricks 35 bricks

Average 30 bricks 33 bricks 34.5 bricks

These results show that the colder the temperature of a bottle of coke the higher a Mentos eruption goes. This is significant because it shows that a temperature change has a certain effect on the eruption. A great follow up experiment that could be done would be how the eruption would be affected if you heated up the soda as opposed to cooling it down. If this experiment was conducted following the experiment where the soda was cooled down then you could see how temperature affects Mentos eruptions on a much bigger spectrum. This experiment was relatively reliable, and issue being that some of our sodas were on the wrong angle with the wall and one even fell down. For these reasons out experiment could not be called completely valid. Although when our sodas fell over and hit the wall the wrong way we repeated these bottles and got more valid results. The difference in these temperatures did not prove to be huge but definitely had somewhat of a difference. Since the change in height from room temperature to 8 degrees 9

Celsius was 9% this proves that there was some height involving the change in temperature. Meanwhile the change from 8 degrees Celsius and 3 degrees Celsius was a lot less drastic with a change in height of only 3%. For this reason it cannot definitely be proven that there is a huge difference between 8 degrees Celsius and 3 degrees Celsius. Some other interesting articles involving Mentos eruptions are about the discoveries made by Marsh and Moalli who kept and eruption going for 40 seconds and how Federici and LaChance found that cinnamon Mentos erupted 20% higher than any other flavor. 1. 2. 3. 4. 5.

Gather Materials- 45 Mentos, 9 bottles of coke, geyser tube, way of measuring Make 3 bottles of coke room temperature (22â °C) make 3 bottles 8â °C and make 3 bottles 3â °C. Put 5 Mentos in a geyser tube and align coke bottle with measuring tool. Drop Mentos into the bottle and record results Repeat this for each of the nine bottles

Mint Mentos Erupt 16% Higher Than Strawberry Mentos and 55% Higher Than Green Apple Mentos with Diet Coke Anny Y I. SUMMARY The purpose of this experiment was to investigate which flavor of mentos created the highest eruption with diet coke. There were three different flavors of mentos tested: mint, strawberry, and green apple. There were two trials performed for each mentos flavor. The height of the eruptions was measured by counting the amount of bricks the eruption’s spray reached on the side of a building. The results, in meters, were calculated by the formula: height of 1 brick=2.25 inches=0.05715 meters. The results for the mint mentos were 4.7 meters (82 bricks) and 4.0 meters (70 bricks) with an average of 4.35 meters. The results for the strawberry mentos were 3.4 meters (60 bricks) and 3.9 meters (68 bricks) with an average of 3.65 meters. The results for the green apple mentos were 1.9 meters (34 bricks) and 2.0 meters (35 bricks) with an average of 1.95 meters. These results show that the mint mentos erupted 16% higher than the strawberry mentos [use of formula: 1 – (3.65/4.35) = 0.1609 ] and that the mint mentos also erupted 55% higher than the green apple mentos [use of formula: 1 – (1.95/4.35) = 0.5517 ]. II. INTRODUCTION Diet coke-mentos eruptions are becoming a popular experiment in the world of science. The experiments include dropping about 5-10 mentos into usually a 2 L bottle of diet coke. The result is a large eruption of the diet coke spray, which is referred to as a geyseri. Interestingly enough, the mentos reaction is said to be a physical reaction and not a chemical one because when the mentos hit the soda, bubbles are formed over its surface, and the liquid is pushed out of the bottle in a violent eruptionii. What specifically causes the enormous eruption is still being investigated. Professor Coffey of Appalachian State University performed the mentos experiment, but first investigated the popular Mythbusters team’s experimental claims and eruptions which are posted all over the internetiii. Coffey’s report states that the Mythbusters correctly identified aspartame and potassium benzoate as the two key ingredients to set off the large eruptionsiv. The report also acknowledges different variable that may have an effect on the eruptions. It’s interesting to see just how many ways the experiments can be formed and what information can consequently be pulled from them. For example, not only diet coke has to be used in an eruption. Musterer and Ruotolo from The Guilford Journal of Chemistry conducted experiments and discovered than diet pepsi created an eruption 100% higher than that of the diet cokev. Another interesting experiment was that of Taylor and Schaffer, who discovered that a melted mentos will erupt at a slow rate that can sustain for hoursvi. This is very different from the other experiments because it measures not the height of an eruption, but how long it sustains for. Similarly, the experiment by Earles and Graham suggested that eruption power should be measured by volume of the eruptionvii. In their findings, the remaining soda volume for many soda sizes was constant which suggests that there is a fixed relationship between soda size and eruption volumeviii. Another experiment by Feldman and Monte, suggested that the more mentos added to the experiment, the higher the eruptionix. A final experiment similar to the one explored in this lab is that of Federici and LaChance, which suggested that cinnamon mentos eruptions are 20% higher than mint mentos eruptionsx. III. EXPERIMENTAL SECTION / PROCEDURE There were three levels of the independent variable in this experiment, which were mint mentos, strawberry mentos, and green apple mentos. There was no control in this experiment. The constants in this experiment were the amount of diet coke used in each eruption (2 L), the amount of mentos used in each eruption (10 mentos), and the distance from the diet coke bottle to the wall (1 ft). The dependent variable was the height of the eruption, measured in bricks and then converted into meters. Materials for the experiment included 6 2 L bottles of diet coke, 2 rolls of mint mentos, 2 rolls of strawberry mentos, 2 rolls of green apple mentos, an eruption chamber (dry). The procedure used to perform this experiment was: 11

Place 2 L diet coke bottle 1 foot from the brick wall and angle slightly toward the wall so that the spray will hit the wall but still reach maximum height. Open the eruption chamber tube and insert 10 mint mentos. Close the tube. Open the diet coke bottle and quickly screw the eruption chamber onto the top of the bottle until it is completely tight. Pull the string on the side of the chamber to release the mentos into the diet coke, and step back. Observe the eruption and count how many bricks tall the eruption reached. Repeat steps 1-5 with a dry chamber for a second trial. Repeat steps 1-6 with the strawberry mentos. Repeat steps 1-6 with the green apple mentos. Record all data and convert brick measurements into meters using formula: 1 brick=2.25 inches=0.05715 meters.

IV. RESULTS The results for the mint mentos were: trial #1- 4.7 meters (82 bricks); trial #2- 4.0 meters (70 bricks); an average of 4.35 meters. The results for the strawberry mentos were: trial #1- 3.4 meters (60 bricks); trial #2- 3.9 meters (68 bricks); an average of 3.65 meters. The results for the green apple mentos were: trial #1- 1.9 meters (34 bricks); trial #22.0 meters (35 bricks); an average of 1.95 meters.

Height (cm)

Average Height 600 500 400 300 200 100 0 Average

Type of Soda

5 4.5

Mint Mentos Erupt 16% Higher Than Strawberry and 55% Higher Than Green Apple

Height of Eruption (meters)

4 3.5 3 Trial 1

2.5

Trial 2

Average 1.5 1 0.5 0 Mint Mentos

Strawberry Mentos

Green Apple Mentos

Type of Mentos

V. CONCLUSION The results found in this experiment show that mint mentos had an average eruption 16% higher than strawberry mentos, and also an average eruption 55% higher than green apple mentos. The reason for these results could be due to different textures of the different flavored mentos, the different ingredients used for the different mentos, a different level of gum arabic in the mentos, or many other explanations. Ultimately, this experiment cannot provide a reason for the results. These results are not so significant that it would be assumable that mint mentos cause the highest diet coke-mentos eruptions. The validity of the experiment is not exemplary due to the amount of variables present in the experimental conditions. For example, there was no constant launching angle that the diet coke bottle was placed in. This would have affected height of the eruption sprayed on the bricks, because it would have angled the line of spray differently for each trial. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed launching angle of 40 degrees between the bottle and the ground near the wall. Another variable that could have poorly affected the results is the different time periods after opening the diet coke bottle. Between opening the bottle and letting the eruption go off there is a period of time where CO2 gas is leaking out of the soda. This would have affected the experiment by making the eruptions that had a longer time period weaker than those that had a shorter time period. A future recommendation to avoid this issue would be to set up a similar experiment but with a fixed amount of time of 15 seconds recorded and issued by a stopwatch between the opening of the soda bottle and the actual eruption.

Account of mentos-like eruptions dating back to the 1980s with an interview of Steve Spangler at http://www.rimmkaufman.com/blog/steve-spangler/21122007/ ii Steve Spangler article about what happens to the ingredients during a diet coke-mentos reaction at http://www.stevespanglerscience.com/experiment/original-mentos-diet-coke-geyser iii Mythbustersâ&#x20AC;&#x2122;s mentos experiments recorded in video at http://dsc.discovery.com/videos/mythbusters-diet-coke-andmentos.html iv Tonya Shea Coffey report on what is behind the mentos reaction and the validity of the Mythbustersâ&#x20AC;&#x2122;s claims at http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf v Angelise Musterer and Lindsay Rutolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). vi Sam Taylor and Will Schaffer, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008). Dr. H. Brielmann, The Guilford Journal of Chemistry, Volume 1, pages 4-5 (2008). ix Matt Feldman and Alex Monte, The Guilford Journal of Chemistry, Volume 2, pages 29-31 (2008). x Allison Federici and Jess LaChance, The Guilford Journal of Chemistry, Volume 2, pages 15-16 (2008). vii

viii

Increased Temperature of Diet Coke and Number of Mentos Increases the Height of Mentos Eruption Anna K The hypothesis of this experiment was, If more mentos are used in an eruption when Diet Coke is at a higher temperature, then the eruption will be higher because there will be more matter being exerted from the bottle with a higher pressure. We completed six trials. These trials included increasing the temperature of the soda while at the same time increasing the number of mentos to see what difference, if any, would occur when these changes are made. 3 of the bottles had 4 mentos used, and 3 different bottles had 6 mentos used. One bottle of each was at a temperature of 298.15 K, one was 301.95 K, and one was 304.15K. The trial which had the results that most supported the hypothesis was the Diet Coke soda bottle which was at a temperature of 304.15 K and 6 mentos used, which had the highest eruption. The trial which least supported the hypothesis was the Diet Coke bottle at a temperature of 298.15 K and 4 mentos used, which had the shortest eruption. The eruption was measured by how high the soda sprayed against the wall. Each brick is equal to 5.5 cm, so the equation for figuring out the height of the eruption is: Number of bricks high × 5.5 = height of eruption. We counted the number of bricks and then used this formula to find the exact height in centimeters. Then we recorded the data and repeated this process for every other trial we had to complete. “The warm diet coke’s results sky-rocketed. Of the two warm test trials, both blast the coke into the air with a large amount of force, resulting in an average height more than double what the room temperature soda achieved.” ¹ This excerpt from the Guilford Journal of Chemistry supports the hypothesis by stating, like the hypothesis, that more force from the heightened temperature increased the height of the eruption. When four mentos were used with a soda temperature of 298.15 K, the eruption reached 440 cm. When four mentos were used with a soda temperature of 301.15 K, the eruption reached 473 cm. And when four mentos were used at 304.14 K, the eruption reached 473 cm as well. We then tested with the same temperatures, but with 6 mentos. When the soda was at a temperature of 298.15 K, the eruption reached 451cm. When the soda was at 301.15 K, the eruption reached 484 cm. And when the soda was at 304.15 K, the eruption reached 495 cm. There was an increase of height of eruption when 6 mentos were used rather than four. For example, at 298.15 K, there was an 11 cm increase. At 301.15 K, there was also an 11 cm increase. And at 304.15 K there was a 22 cm increase. “By the results of the data, it is easily safe to conclude that the warmer the diet coke temperature, the more height the eruption gained.” ² This also corresponds with the data obtained in this experiment, and it agrees with what was found within the data. And it could be concluded that the warmer the diet coke, the higher eruption occurred as well. “Our results clearly support the theory that using warmer Diet Coke will result in a higher Mentos eruption. Each time we raised the temperature of the soda, the result was a taller eruption, with our warmest bottle’s eruption reaching six meters! This can certainly be taken as proof that raising the temperature of Diet Coke affects the eruption size. However, a follow-up experiment where multiple trials are used would be a good idea to test the consistency of this fact” ³ Each time the temperature increased, the eruption increased regardless of how many mentos were used. But a significant increase was observed when 6 mentos were used rather than only 4. Although the data showed a definite conclusion, the data would be more precise and reliable if multiple trials were conducted. In the essay by Tonya Shea Coffey, it stated how Diet Coke heated to a temperature of 320.15 K lost 170 more grams of mass than Diet Coke chilled to a temperature of 279.15 K. 4 The loss of mass signifies the amount of matter exerted from the bottle, which means 15

that a greater eruption occurred when the Diet Coke was at a much higher temperature. “The temperature of the soda greatly affects how much force and height the geyser of soda fizz will shoot up to.” 5 The highest temperature used in the experiment also had much more force resulting in a higher eruption, and it shot up much higher. We placed each Diet Coke bottle into their own separate tub of water heated to specific temperatures (298.15 K, 301.15 K, and 304.15 K). Once at the correct temperatures, they were taken outside and set up against the wall and geyser tubes with either 4 or 6 mentos (depending on which trial) were tightly attached to the nozzle of the soda bottle. The eruptions were promptly set off after the bottles were open to ensure the most amount of pressure would be exerted. Then the height of the eruption was measured by counting the number of bricks high, and then using that along with the formula stated above to find the exact height of the eruption in centimeters. After reviewing the data from the experiment the conclusion is able to be made that the temperature of soda has an effect on the height of a Mentos eruption. As expected, the warmest soda had the highest eruption. [i]In the first 3 trials when we used only 4 Mentos for each different temperature, the heights of the explosions got higher for each trial; as the temperature was higher for each trial. The first trial when the soda was at 298 kelvin the eruption reached 440 cm. On the second trial when the temperature was 3 kelvin higher at 301 kelvin, the eruption reached 473 centimeters which is a great deal higher than the first trial. On the third trial however, when the soda temperature was 304 kelvin the height of the eruption stayed constant at 473 centimeters. However this may be due to error in the experiment, because in our second set of trials the third trial produced a higher eruption of 495 cm than at the second trial at 484 cm. This data is closely related to Justin Husted’s experiment from the Guilford Journal of Chemistry. The room temperature soda in his eruptions had expected results and was a relative increase from the cool soda. The warm diet cokes results sky-rocketed. [ii] When comparing results of this experiment to Justin Husted’s similar experiment, his data suggests the same overall conclusion. The final trial of his experiment was of the warmest soda which was heated in water measured at 308 degrees kelvin. The resulting reaction resulted in an eruption of 300 centimeters which was his highest.[iii] By the results of his experiment it was easy to declare that the temperature of soda does have an effect on Mento eruptions.[iv] Due to a kink in the data I collected, I cannot easily state the same with an equal amount of confidence but, my overall collection of data does suggest it.

[i] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [ii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iii] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print. [iv] Husted, Justin. "Warm Soda Has a Dramatic Effect on the Height of a Mentos Eruption." Guilford Journal of Chemistry 1.1 (2008): 19-20. Print.

Two Bottles of Diet Coke Connected to Make One Eruption Will Heighten the Eruption Compared to a Single Eruption Ambur D When two bottles of regular diet coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption. When having nine mint mentos added to a single bottle of Diet Coke, the average eruption height will be 433.2cm. When dropping nine mint mentos at the same time to each Diet Coke bottle that is connected to cause one eruption, the average height will be 587.1cm. The Mentos Diet Coke eruption is a famous experiment with high school students. Mentos contain certain ingredients that cause this reaction with Diet Coke, or any soda for this matter. “The numerous small pores on the candy's surface catalyze the release of carbon dioxide (CO2) gas from the soda, resulting in the rapid expulsion of copious amounts of foam.”(Wikipedia) The outer coating the Mentos is important to the cause of an eruption. The small holes the Mentos contains allows the carbon dioxide to squeeze through, getting to the middle. “The potassium benzoate, aspartame, and CO2 gas contained in the Diet Coke, in combination with the gelatin and gum arabic ingredients of the Mentos, all contribute to formation of the foam”(Mythbusters). Gum arabic is a natural gum made of hardened sap taken from two kinds of the acacia tree and gelatin is solid substance, brought from the collagen inside animals' skin and bones. Potassium benzoate is an acid with a low-pH level, lower than 4.5 and aspartame is a noncarbohydrate sweetener used as a substitute for sugar. When all of these ingredients are mixed together with the carbon dioxide in Diet Coke, it causes the instant reaction called a geyser. Gather the supplies to complete this experiment. Attach two elbow shaped PBC plumbing pipes to one “T” shaped PBC plumbing pipe to create an upside-down football goal post or an upside-down digital “Y”. Then use Duct Tape to connect and seal the piping to the Mentos geyser tube provided by Steve Spangler (Educational Toys and Science Toys). Insert nine mint Mentos into each geyser tube carefully. Then slide in the stopper so the Mentos don’t fall out premature to the experiment. Unscrew both tops of the two liter Diet Coke Bottles and insert the geyser tubes in less than thirty seconds, otherwise the carbon dioxide will escape from the bottle. Once each geyser tube is inserted and screwed on the two liter bottles, pull each stopper out of each geyser tube at the exact same time to ensure accurate results. It would be wise to do it against a brick wall, that way counting the bricks first and multiplying that number by 5.7 centimeters is easier than just trying to count the height in centimeters. Create a data table with many trials to ensure accuracy and graph these results. The statement; When two bottles of regular Diet Coke are connected to cause one eruption, the height of the eruption will be larger compared to a single eruption, Proves to be true. Although, there is no mathematical way to explain the height difference between a combined eruption and a single eruption, the height was larger. By doubling the amount of carbon dioxide and other Diet Coke ingredients, while adding them to the doubled amount of ingredients in Mentos, essentially created a larger eruption. To ensure more accurate results it is always wise to do as many trials as possible and apply more duct tape to guarantee no leakage. Endnotes "Diet Coke and Mentos Eruption." Wikipedia, the Free Encyclopedia. Web. 12 Oct. 2011. <http://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption>.

"MythBusters: Diet Coke and Mentos Episode Summary - TV.com." TV.com - Free Full Episodes & Clips, Show Info and TV Listings Guide. Web. 12 Oct. 2011. <http://www.tv.com/shows/mythbusters/diet-coke-and-mentos-822481/>. "Geyser Tube." Science Projects Experiments, Educational Toys & Science Toys. Web. 12 Oct. 2011. <http://www.stevespanglerscience.com/product/geyser-tube>.

Period 3

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption Catherine D The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didnâ&#x20AC;&#x2122;t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffeyâ&#x20AC;&#x2122;s results and test the effectiveness of adding baking soda to the diet coke. According to Coffeyâ&#x20AC;&#x2122;s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters. We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment 1.

Gather all Materials needed for the experiment

Using a tube that can release objects with the pull of a string, and place five mentos within the tube.

3. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured 4.

Measure how high the soda shot upwards, and record the results; this will be your control

Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process

Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process

Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process

Compile the data and graph it

Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Conclusion Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction. According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar. A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high. Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective. An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke. Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment. In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip over , make sure that the bottle wasn’t shaken around before performing the experiment, and make sure that you’re using all the same flavor Mento’s for the same trial.

Mentos Soaked in Club Soda Prior to Trial Will Cause the Highest Eruption Claire W and Lindsey U

Summary According to the data, soaking Mentos will decrease eruption height from Mentos not soaked in anything, the control of the experiment. However, the highest eruption height came when the Mentos were soaked in club soda for one minute and left to dry for three. The average eruption height in bricks was 16.8 for club soda after three trials were conducted. There was about a 35% decrease from the control eruptions, which had an average eruption height of 26 bricks. Mentos soaked in saliva for a minute, left to dry for three minutes prior to the trial had average eruption height of 14 bricks and a 46% decrease from the control height. Mentos soaked in Diet coke for one minute and left to dry for three minutes had an average eruption height of 8.5 bricks and a 67% decrease from the control height. Mentos soaked in Pepsi for one minute and left to dry for three minutes had an average eruption of height of 6.17 bricks and a 76% decrease in eruption height from the control. Finally the smallest eruption was the result of Mentos soaked in a sugar solution of Splenda and water solution for one minute and left to soak for 3 minutes prior to trial had an average eruption height of 3 bricks and an 88% decrease in height from the control. Overall the additives that the Mentos were 21

soaked in lead to significant decreases in the heights of the eruptions. There was no significant pattern found in the data because it tested additive solutions and not quantitative changes, therefore a mathematical formula to describe these reactions would entail as follows: E=eruption height A= solutions that Mentos were soaked in and M=The Mento itself. So the simple equation is, M+A=E.

Introduction This unique experiment used to measure the height of an eruption soaked in a solution was created based on the results of Tonya Coffey, the professor of the Department of Physics and Astronomy at Appalachian State University. Coffey found that the significance of the ingredients caffeine, potassium benzoate, and aspartame in Diet Coke, and the gum Arabic and gelatin in Mentos which led to a higher eruptionx. In this experiment, many of the solutions used were of different sodas. Just like the findings of Shore and Brownx, Diet Coke did not have the highest eruption, Sprite Zero did. The findings of Musterer and Ruotolox also find that Diet Coke did not have the highest eruption, but Diet Pepsi did. These similar findings show that other solutions other than Diet Coke can have a higher eruption. In another experiment similar to this experiment, by Clark and Agamiex, their control had the highest eruption without any coating. This probably means that soaking a mentos in solutions probably wonâ&#x20AC;&#x2122;t increase the eruption height. According to the findings of Hustedx, the cooler the soda, the smaller the eruption. The results of Husted were also supported by the results of Melillo and Guryanovx, who concluded that the higher the temperature the bottle is heated, the higher the eruption. This probably means keeping the diet coke at room temperature or higher will improve eruption 22

height. In this experiment, it was made sure that the soda was not cooled because of these findings. According to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles. to Moalli and Marshx, the ingredients in Mentos like gellan gum and gum Arabic cause a higher eruption because they dissolve, break the surface tension, and makes it so it is less work to expand and form new bubbles.

Experimental Section This experiment tested the effect of different solutions on Mentos when they were soaked and left to dry before an eruption. Club Soda, Human Saliva, Diet Coke, Pepsi, and a sugar and water solution was tested against a control. First a control was tested three times, where one Mento was dropped into an 8 ounce of diet coke through a geyser and made an eruption against the brick wall. Next, Mentos were dropped into cups filled with half a cup of each solution, and left to soak for approximately one minute. Then they were removed and were left to dry for approximately three minutes, leaving a coat of the specific solution on each Mento. After quickly opening the 8 ounce bottles one of the Mentos was then dropped into the geyser tube where it was then dropped into the Diet Coke to create and eruption which was measured against a brick wall. After three trials with each solution the data was recorded and the average was found, along with the percent decrease in eruption height from the control. Results

The Effect Soaking Mentos in Different Solutions has on Height Eruptions

Height in Bricks

29 25 2426 17.5 1816.8 16 15 14 14 12

20 15 10

Trial 1 11 8.5 8.5 6

Trial 2

9.5 7

Trial 3

6.17 3

5 1

0 Control

Club Soda

Saliva

Diet Coke

Pepsi

Splenda Solution

Solutions that Mentos Were Soaked

% Decrease from Control 100 80 60 40 20 0

67 35

0 % Decrease from Control

Average

Conclusion The results of this experiment show how different solutions or additives can deter a Mentos and Diet Coke eruption. It is important to consider the ingredients in each solution that the Mentos were soaked in, and how it directly relates to the results, the idea relates to the idea of Federici and LaChancex that mint Mentos have the highest eruption height because of their flavoring. Club Soda most likely made the highest eruption out of all substance coatings tested because it doesnâ&#x20AC;&#x2122;t contain sugar, most likely a major factor in why Coke and Mentos react together. This would explain why the Splenda solution had the lowest reaction, because the Mento would be coated with a sugar coating after coating. Therefore the higher the amount of sugar on a Mentos coating directly deters eruption height. Further experiments could entail picking out specific ingredients and soaking Mentos in them other than just picking certain solutions. This would clarify what additives to each substance cause the reaction rather than in this experiment where only the solutions themselves were tested. If conducted with sugary ingredients and non-sugary ingredients this experiment would prove the statement made in the previous paragraph. Experimental Procedure 1. Find a control height (no soaking in any solution) by dropping one Mentos in a 8 oz. Diet Coke bottle 2. Record the height of the eruption 3. Soak 1 Mento in Club Soda (Approximately one minute) 4. Wait for Mento to dry (Approximately three minutes) 5. Drop Mentos in 8 oz. bottle of Diet Coke from geyser 6. Measure height of Eruption (Number of Bricks) 7. Record in data table 8. Repeat process until completing 3 trials 9. Repeat steps 1-5 with saliva, diet coke, pepsi, and splenda solutions

How the Size of the Hole in the Nozzle Affects the Height of a Coke and Mentos Eruption Shane G and Clara P

Summary: The objective in this experiment was to see if the holes size in the nozzle would affect just how high the coke would reach when mixed with Mentos. We believed that as the hole got smaller then the coke would shoot higher because more pressure would be forcing the coke out. The pressure would build because the coke would not be able to escape as easily. However, we also believed that once the hole got to a certain point, of being too small, then the geyser would not reach as high because the stream would be too small to give a good push through the air, or because the intense pressure would simply cause the bottle to spray it out, rather than have it stream out, or the bottle would simply explode. (From the findings of previous experiments done and put on Wikipedia (http://en.wikipedia.org/wiki/Soda_and_candy_eruption)) Because of 26

this safety hazard, we were unable to create a hole that small. What we did find, using our four diameter measurements of 2.0 cm, 1.5 cm, 1.0 cm, and 0.5 cm, was that as the hole gets smaller the streams height would increase which proved our original hypothesis. Using two mint Mentos per trial, we found that the average height for the 2.0 cm hole was about 5.25 bricks high which is only 13 % of the largest average. The 0.5 cm hole shot an average of 39.75 bricks high. The 1.5 cm hole shot an average of 13.75 bricks, which is 35 % of the largest, while the 1 cm hole reached an average of 24.75 bricks which is about 62 % of the largest heights average. This proves our original hypothesis that a smaller hole will produce a larger height. Introduction: The Coke and Mentos reaction has been around since the 1980â&#x20AC;&#x2122;s but was first widely introduced to the world on the David Letterman show in 1999. Since then there have been numerous videos and records of this type of eruption. In recent years more research has been done and even televised on shows like Time-Warp and Mythbusters. The Guilford Journal of Chemistry has included very conclusive experiments including those by Cutler and Smith who found that the temperature of the Mento can greatly increase the height. We believe that this could have some affect on the nucleation sights on the Mento which are believed to be the true cause of this reaction. We now set out to find our own way to increase the height of the eruption by building pressure in the form of less area for the soda to escape from.

Experimental Section: Materials: 1. Coca-Cola (all the same sized and shaped bottles, with the same amount of liquid.) 2. Drill or some way to cut an accurate and precise hole into the caps 3. A ruler 4. A lot of Mentos (use the same number and kind for each trial â&#x20AC;&#x201C; we used two mint per trial) 5. Pencil and Paper for recording data 6. Way of measuring the height (we used the bricks of a wall that the Coca-Cola shot up against) 7. Duct Tape 8. Paper towels or a small cleaning rag Variables and Constants: Independent Variable: Size of the Hole in the Nozzle or Cap Dependent Variable: Height of the Eruption Constants: Since we did the majority of our tests within the same hour a few constants include the temperature of the coke and of the Mentos, the temperature outside, and the amount of wind stayed fairly 27

consistent throughout our time. Others include the type of Mento, the amount of Mentos per drop, the height of the drop, the angle the geyser tilted at, the bottle shape and size, and the amount of soda per bottle. We tried to keep the time between opening the cokes and dropping the Mentos as consistent as we could but there was no real accurate way of telling so I would like to change that next expieriment. Procedure: 1. Cut the holes into the caps, 0.5 cm, 1.0 cm, 1.5 cm, 2 cm diameters. (try to make the holes as clean cut as possible. Note that the geyser tubes original cap is about 1 cm wide and the tube without a cap is about 2 cm wide so the only ones really needed are the 1.5 and the 0.5 cm holes) 2. Wipe inside of geyser so Mentos do not stick with paper towels or a cleaning rag 3. Make sure the 0.5 cm cap is secured to the geyser 4. Flip over and put in two Mentos 5. Insert the key and flip back over 6. Open coke and secure geyser onto the top 7. Set down near a wall or measuring tape and release Mentos 8. Record height 9. Repeat two or three times (depending on supplies) 10. Repeat steps 2-9 for 1.0 cm, 1.5 cm, and 2 cm, diameter holes

Results: Hole Size (Diameter)

Hole Size (Area â&#x20AC;&#x201C; cm2)

Trial 1 (Bricks)

Trial 2 (Bricks)

Trial 3 (Bricks)

Trial 4 (Bricks)

Averages (Bricks)

Percents

2 cm

3.142

5.25

13%

1.5 cm

1.767

13.75

35%

1 cm

0.785

24.75

62%

.5 cm

0.196

39.75

100%

These numbers show us that the smallest hole gives us the largest height for the stream of coke. The 2 cm diameter hole only reached an average of 5.25 bricks while the half a cm gave us an average of 39.75 28

bricks. The second largest hole had the second smallest height average of 13.75 cm while the second smallest hole had the second largest height average of 24.75. The three larger holes only reached a small percentage of the same height as the smallest hole showing that the smaller the hole is the higher the geyser will reach. (Graph in back) Conclusion: With the numbers previously recorded and discussed slightly we can conclude that as the hole got smaller, the coke would shoot higher because the high amount of pressure would be forcing the coke out in fast, tall upward motion. (Data from Holly Aery and Adam Sierzputowski, found in The Guilford Journal of Chemistry) As the hole size in the cap gets smaller the stream gets higher. This is very important because the original goal of all our experiments was to see how we can achieve the largest coke and Mentos eruption height. Many other tests were conducted by our fellow classmates trying to prove the same thing. They tested ideas such as types of Mentos, amount of Mentos, the height you drop the Mentos from, the temperature of the coke and of the Mentos, and even if there is a different type of drink that will make the eruption higher. We found that when the hole gets smaller the average height of the eruption will grow as well. A hole with a diameter of 2 cm only reached an average of 5.25 bricks off the ground. (We made the eruption next to a wall so we could measure the eruption based off the bricks as shown in the images below.) The second largest hole, 1.5 cm, reached an average height of 13.75 bricks. The third largest at 1 cm made it to an average of 24.75 bricks. Lastly, the smallest hole, with a diameter of only half a cm, reached an average height of 39.75 which is about 161% higher than the 1 cm diameter hole. The reason the smaller hole reached higher is because there is less of an opening for the soda to escape from meaning there will be more pressure forcing it out. However, we believe, due to this fact that if the hole is too small, then the pressure could theoretically become so intense that it would either shoot the cap off or cause the bottle to explode. (As explained in The Nozzle video on Youtube (http://www.youtube.com/watch?v=Q2tAGH2E_Bk) This is why we were unable to go to any size lower than half a cm. We would like to conduct a follow up experiment in a safer location where We can make the hole even smaller to see if it will just spray, form an actual stream, or explode. If this were to happen it would disprove our conclusion showing that there is an optimum sized hole for the maximum height. We would also like to do a follow up experiment on the Cutler and Smith experiment to see if it is instead the difference in temperature between the liquid and Mento.

References:

1. "Diet Coke and Mentos Eruption." Wikipedia, The Free Encyclopedia. 2011. October 8th, 2011. http://en.wikipedia.org/wiki/Soda_and_candy_eruption (Used in background and outside information on mentos eruption) 2. Holly Aery and Adam Sierzputowski. The Guilford Journal of Chemistry. Volume 2. Pages 23-26. (2011) (Helped to compare our findings to those of previous research, as well as helping to give data to our conclusion.) 3. "The Diet Coke Nozzle Test." Youtube. June 29th, 2007. Viewed in September-October 2011. (Gave an idea of what to expect, as well what what materials to buy, and helped in formation of hypothesis

The height of the Mentos eruption depends on the outside coating Jenna P

Summary: In our experiment, we discovered that the coating on the outside of the Mentos affects the eruption height. We put Mentos with coating and recorded the results however we then took Mentos that were sitting in water for a while and saw the eruption height. There was a drastic difference. With the coating we got results of 16, 21, and 25 bricks. Without the coating we had results of 3, 7 and 9 bricks. We therefore noticed that the coating of the Mentos affects the eruption height.

Introduction: During our experiment we took regular mint Mentos and compared the eruption height to Mentos without the coating on. Our hypothesis was, if we soak the coating off the Mentos then the eruption height would be affected drastically because the coating makes the soda fizz more. Our hypothesis was proven with the results we took. We didnâ&#x20AC;&#x2122;t tamper with the Mentos for the results of the Mentos with the coating, they were left normal. However, the Mentos with no coating were soaked in water to get all the coating off. To receive the results of the Mentos with coating we put 6 into the geyser and pulled the latch received varied results. We then took the Mentos soaked in water put six in the geyser and pulled the latch the same way we did with the coating and received varied results.

Experimental section: 1. Take 6 coated Mentos out of the package and transfer them into the soda geyser. 2. Take 6 Mentos and put them into a cup of water. 3. Then pull the latch to transport the Mentos in the geyser into the soda. 4. Observe what is going on and the height of the eruption. 5. When the eruption is finished count how high it went by counting the bricks. 6. Repeat steps 1-4 2 more times. 7. Take the Mentos from the water out and transfer then into the soda geyser. 8. Pull latch on geyser. 9. Observe eruption from Mentos without a coating. 10. Record results by counting the bricks to see the height of the eruption. 11. Then repeat 7-10 2 more times.

Results: Mentos: With outside coating Without outside coating

First trial 16 bricks 3 bricks

Second trial 21 bricks 9 bricks

Third trial 25 bricks 11 bricks

Our results were varied however all within a range. The Mentos with a coating had results between 15 and 25. Our first trial was the smallest eruption with a coating; it only went the height of 16 bricks. The second trial went the heights of 21 bricks, just a little higher than the first trial and our third and last trial received heights of 25 bricks and was the highest eruption height. Our results without an outside coating of the Mentos varied between 1 and 15 bricks. The first trial without a coating only went the height of 3 bricks and was the lowest eruption height we received. The second trial was 9 bricks and the third and last trials height was 11 bricks high and was the highest eruption height with no outside coating.

Conclusion: In the Mentos eruption experiment our results were clear that the outside coating affects the height of the eruption. We discovered the outside coating is the most important part to a Mentos and soda eruption. We received really high numbers with an outside coating compared to the Mentos without a coating. In other experiments we could find exactly what is causing the eruption and what is in the outside coating making the difference in the height.

Diet Coke VS. Energy Drinks Marguerite D and Alex P

Summary: In the lab, “Diet Coke vs. Energy Drinks”, we modified the classic Diet Coke and Mentos Eruption experiment by testing the Diet Coke’s eruption height in comparison to popular energy drinks, Rockstar and Monster. Diet Coke’s results suggested that Diet Coke was in fact better suited for the experiment. Diet Coke had an average eruption height of 13.5 bricks (40.5 inches). Monster came in second place with an average height of 8 bricks (24 inches), while Rockstar trailed behind with an average eruption height of 7.5 bricks (22.5 inches). These measurements resulted in a 57.4% difference between the Diet Coke and the energy drinks. These results did not support our original hypothesis that energy drinks would be better suited for the lab because of their assumed carbonation levels. Introduction: The Mentos Eruption Lab is a classic experiment where different carbonated beverages are examined to see which would produce the highest eruption height when combined with several Mentos. The Diet Coke and Mentos Lab is popular because “it inspires students to wonder and inquiry-driven labs/active-learning demonstrations on this reaction have been implemented.” [1] For the Mentos-Diet Coke reaction, the carbonic acid and carbon dioxide are not products of a chemical reaction but are already present the Diet Coke, whose equilibrium is disrupted by the Mentos. [2] The reaction to the Diet Coke occurs when several Mentos are dropped into the carbonated beverage. Though “numerous theories have been purported to explain the science behind the Mentos eruption”[3], we have come to believe that it’s due to the pressured carbonation being released by the disruption of the Mentos. Some say that “Depending on the number of Mentos dropped into the bottle, the spray height can vary between a few inches and tens of feet”[4]. However, we went in a different direction and made a slight change to the classic experiment by testing the eruption height of energy drinks, Monster and Rockstar. We were looking to prove, like the several unverified explanations of the experiment that have been offered to explain the experiment[5], that energy drinks carbonation would produce a higher eruption height than the original Diet Coke. Materials:  2 cans of Monster Energy Drink  2 cans of Rockstar Energy Drink  2 1L bottles of Diet Coke  3 rolls of Mentos  4 coke bottle nozzles  1 geyser tube  Duct tape 33

Procedure A: 1. 2. 3. 4. 5.

Take Coke bottle nozzle from a Coke bottle Attach geyser tube to the bottle nozzle Use a can opener to remove the top of the energy drinks can completely Use duct tape to securely fasten the Coke bottle nozzle to the top of the can Make sure to do this as fast as you can so you donâ&#x20AC;&#x2122;t lose too much carbonation

Procedure B: 1. 2. 3. 4. 5. 6.

Dress the Coke bottle up with the geyser tube so it is secure. Fill geyser tube with 4 Mentos. Pull geyser tube string to release the Mentos Back away from the eruption Repeat steps 1-4 and record results For the Monster and Rockstar portion, begin with Procedure A and follow steps 1-5 accordingly.

Data Table: Diet Coke

Monster

Rockstar

Trial 1

13 Bricks

9 Bricks

8 Bricks

Trial 2

14 Bricks

7 Bricks

Average

13.5 Bricks

8 Bricks

7.5 Bricks

Conclusion: After two trials for each beverage, Diet Coke’s average height results of 13.5 bricks trampled the results of Rockstar’s 7.5 and Monster’s 8 bricks. This thoroughly disproved our hypothesis of the Energy Drinks having a higher success height than Diet Coke because of their carbonation levels. The failure of the Energy Drinks could be attributed to the fact that the cans release the majority of the carbonation. Something to attempt the prevention of this in the future would be to modify the top of the can so you can fit the Mentos in without completely removing the top. This might preserve the carbonation enough to get past only a few inches.

[1]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[2]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 2

For an informative historical account of the Mentos Eruption, Steve Spangler’s website is recommended: http://www.stevespanglerscience.com/experiment/00000109 [3]

[4]

Diet Coke and Mentos: What is really behind this physical reaction?, Dr. Tonya Shea Coffey, page 1

[5]

Mass literature on the Mentos Eruption cites the website of Fred Senese

Period 4 Crushing Mentos will not make the eruption larger. Sara D and Alexa B

Summary: In our experiment, we crushed eight mint mentos and put four into two liter diet coke bottles. Then we put four non-crushed mentos into two liter diet coke bottles. As a result not crushing the mentos allows the eruption to be larger. Each brick had the height of 2.25 inches. Therefore when the mentos were crushed the first measurement was 78 inches. The second measurement was 72 inches. The height difference was six inches. Having the mentos not crushed during the third experiment had a height of 155 inches. The last experiment had a height of 157 inches. The difference between the heights was 2 inches. The difference between the crushed and non-crushed was 2%.

Introduction: It is said that the theory behind what makes the diet coke erupt is that there is an acid-base reaction because Coke is acidic.1 Some people tried to make an experiment to increase height. The world record is 30 feet and nobody has yet to make it. By trying to get more height people changed the soda type. As it turns out, the diet coke had the highest eruption. 2 What we did was to see if crushing the mentos would affect the height. We were incorrect, keeping the mentos how they are leads to a larger eruption.

Experimental Section: For this experiment we gathered all of our materials that include four two-litter diet coke bottles, sixteen mint mentos, and the device to launch the mentos. After, we set everything up, meaning placing the mentos into the tube then releasing the string. Once the coke erupted we calculated the results.

Crushed mentos

1.8 m

Non crushed mentos

3.9 m

Conclusion: After doing this experiment we found out that not crushing mentos allows the eruption to be higher. We know this because with the crushed mentos the average height was 75 inches. Having the mentos not crushed, the average height was 156 inches. We suggest that maybe after this experiment you can use more mentos (crushed and non-crushed) to increase the height. The reliability of our data is pretty high with some errors. All of our materials were constant and we used the same amount for everything. Though, some errors did occur. We opened the bottle a little early which released some carbon dioxide. Also the bottles could have been shaken. Procedure: 1. 2. 3. 4. 5. 6.

Gather materials: 4 two litter diet coke bottles, sixteen mentos, devices for eruption Set up materials Place 4 crushed mentos into the device Pull the string Count the number of bricks that the eruption hit Repeat steps 3-5 with crushed mentos 36

7. Repeat steps 3-5 without crushed mentos 2 times

References: 1

Reasoning for eruption- http://www.newscientist.com/article/dn14114-science-of-mentosdiet-coke-explosionsexplained.html

Angelise Musterer & Lindsay Ruotolo. Guilford Journal of Chemistry, Vol. 2, pages 1-2 (2009).

3. Guilford Journal of Chemistry, Vol. One, Page 5. (2008)

Www.rimmkaufman/rkgblog/2007/12/21/steve-spangler)

4.http://tnst.randolphcollege.edu/apply10/inst_mats/handouts/EnvSc/Coffey08_diet_coke_and_mentos.pdf

5. http://www.sciencebuddies.org/science-fair-projects/project_ideas/MatlSci_p023.shtml

Mentos Car Eruption Andrew T and Mark L

We discovered that when you put regular Pepsi on a car and put mentos in the tube it make the car move 3 feet from the curb. On the other hand when you put diet Pepsi with caffeine and put mentos in the tube the car only moves 2cm from the curb. After doing three trials of both sodas the number came out similar. The trick is to angle the soda up so the mentos can fall into the soda to cause the eruption. The car didnâ&#x20AC;&#x2122;t go for a long time it was more of a sprint it seemed like to me.

Procedure: Trial one Pepsi- 3 feet Trial one diet Pepsi- 2 cm Trial two Pepsi- 2.5 feet Trial two diet Pepsi- 1cm Trial three Pepsi- 1 foot Trial three diet Pepsi- didnâ&#x20AC;&#x2122;t move Something that Mark and I should have done was made it easier for the Mentos to fall into the soda because some of them would fall in but not all of them witch caused false information. 38

That picture above was of the last trial of the diet Pepsi. As you can see something went wrong and the soda started spraying all over the pavement. If I were to do this experiment again I would change a lot of things. First id get an r.c. car and the body off it and tape a two-liter bottle of coke and see what happens. I believe using more soda would make the car go longer and farther. I would suggest this experiment to a lot of people because itâ&#x20AC;&#x2122;s fun, keeps you entertained, and you can see how high you can get the soda to go. Also playing with mentos and soda is just fun.

Period Five

Drilling Holes in Mentos Will Increase Eruption Height Ben E

Summary The famous Diet Coke and Mentos eruption occurs when Mentos candy is dropped into a freshly opened bottle of Diet Coke, resulting in the famous eruption. Many factors are hypothesized to be behind the reaction, one of which is that the Mentos’s relatively rugged surface provides “nucleation sites” where CO2 bubbles form. Apart from only one accepted article by Professor Tonya Coffey, the study of Agamie and Clark which is printed in the Guilford Journal of Chemistry, and an episode of Mythbusters, there is currently little or no information on this subject. This experiment was conducted to see first-hand how surface area can affect eruption height, including the effect of using “donutMentos,” or Mentos with a hole drilled into the middle. Introduction The experiment was conducted to see how affecting the surface area of Mentos candy would affect the height of the eruption. Smoothed, roughed, normal donut, and smoothed donut Mentos were dropped into 2-liter bottles of Diet Coke. Due to problems with time, the trial involving roughed donut Mentos could not be executed. Experimental Procedure Materials that were used in the experiment include a six-roll pack of Mint Mentos candy, with 20 candies per roll, a sixpack of 2-liter Diet Coke, sandpaper for smoothing and roughing up the Mentos, a screwdriver for working holes into the Mentos, toothpicks for poking holes into the Mentos, and a Spangler’s Geyser Tube for releasing the Mentos and for directing the spray. The experiment was taken against a brick wall with an identifiable white silicone line around 54 bricks off the launch site. Each brick, plus the extra space taken by the mortar, measured 7.35 cm. The independent variable was the affect applied to the surface of the Mentos. The dependent variable was the height of the eruption. The control was un-tampered-with Mentos. Constants were the type of Mentos used (Mint), type of soda and quantity of soda used (2-liter Diet Coke), the temperature of the Mentos and the Diet Coke, and the launch site. Only one trial of each independent variable was done, due to lack of supplies. The procedure is as follows: 1. First, the Mentos has to be prepared according to the trial. Smoothed Mentos were rubbed on sandpaper for about 15 seconds on each side, while roughed Mentos were struck sharply across the sandpaper three times on each side. To make donut Mentos, a screwdriver was used to drill a small pit into each side of a Mentos, and then a toothpick was pushed through one of the pits, coming out the other side and forming a hole. Holes were formed in the Mentos before anything else was done to the surface. Ideally, the Mentos would be frozen at this point, but in this experiment, they were not. 2. The next step is to slip the Mentos into the Geyser Tube. Make sure the pin used to keep the Mentos from falling through prematurely is in place. Put eight of the current trial in the Geyser Tube. DO NOT open the bottle of Diet Coke yet. 3. Place the Diet Coke (unopened!) in the launch site. In this case, the bottle should be placed 15 cm away from the brick wall. Make sure the bottle is exactly upright; it cannot be tilting, or the launch height will be compromised. Make sure that the bottle is not shaken before or now. If it was shaken, it is recommended that the launch be put off at least 16 sec, for the soda to settle down. 4. Now is when the bottle is opened and the Geyser Tube goes on. Be aware, the moment the bottle is opened, the eruption begins to lose its potency because CO2 begins to escape from the open nozzle. Therefore, try to 40

minimize the time spent between the moment the bottle is opened and the launch; preferably about 10 sec. Make sure the Geyser Tube in on securely. 5. Once the Tube is on, stand back, count to three, pull the pin, and run. 6. After admiring the eruption, measure how high the eruption went. In this experiment, bricks were counted to gauge how high the spray flew. Then take off the Geyser Tube, toast to the successful launch, eat a Mentos, and repeat for another trial. Results The lowest of the eruption heights was achieved by the smooth Mentos, which reached a height of 46 bricks, or 352.8 cm. Next in the highest was the roughed Mentos, for despite tipping towards the wall, managed to reach up to 49 bricks, or 374.9 cm. Both the normal and the smoothed donut Mentos reached 59 bricks, or 433.7 cm, tying the two trials for the highest eruption height. The roughed donut Mentos trial was skipped, due to lack of time. The control trial, the normal Mentos, reached 51 bricks, or 389.6 cm. A graph for the data is available later in the report. Conclusion and Discussion Taking all of this data, it can be concluded that increasing the surface area of the Mentos will increase the height of the eruption, especially if a hole is poked through the middle of it. The smoothed, non-donut Mentos had the lowest eruption height of the trials at 352.8 cm, and the donut Mentos, both normal and smoothed, had the highest at 433.7 cm. It verifies the hypothesis that increasing the surface area of Mentos candies before dropping them into Diet Coke will increase the eruption height. It also correlates with the data from two other studies, Professor Coffey’s and Agamie and Clark’s. Coffey’s experiment was taken to test a whole slew of hypotheses about the Mentos eruption, one of which was how surface area affects the length of the eruption. They comfirmed that altering the roughness of the surface of the Mentos will increase the explosiveness of the reaction. Agamie and Clark’s study tested the effect of removing the coating on Mentos versus dipping them in dishwashing fluid on the height of the eruption. They found that they were both were surpassed by the control, which was normal Mentos. This is not surprising; removing the coating from the Mentos will essentially make the surface of the Mentos smoother, while dipping Mentos in dish soap will fill the nucleation sites present on the candies. Another study that can be pointed out is that of Marsh and Moalli, who tested the effect of applying different coatings on Mentos. However, since the dependant variable was the length in time of the reaction and not the height of the eruption, it has little significance to this study. Be aware that during the trial for roughed, non-donut Mentos, the bottle tipped, bringing the spray to bear against the brick wall. This caused the eruption height to go down, putting it below the control’s. Also, the trial for roughed, donut Mentos could not be executed, due to a lack of time. It would be worthwhile to come back and do a trial testing it. Overall, despite a couple of discrepancies, this study’s results matches those found by two others, and concludes that affecting the surface area of Mentos candy will increase the height of the spray.

The Graph: 450 430 410 390 370 350 330 310 290 270 250 Control

Smooth

Rough

Donut

Smooth Donut

Roughed Donut (N/A)

P.S. Due to some technical difficulties, it was not possible to label either axis. The x axis is the affect applied to the surface of the Mentos, while the y axis is the eruption height, in centimeters.

The Effect of the Height of Introduction of the Mentos into the Diet Coke on the Severity of the Reaction Dan F and Samuel W

Summary In our experiment, we attempted to adjust the entry level of the Mentos into a 1 liter Diet Coke bottle. Unfortunately, we were unable to get viable results because of faulty engineering. Introduction In an experiment that appeared in the paper â&#x20AC;&#x153;Diet Coke and Mentos, What Is Really Behind This Physical Reaction?â&#x20AC;?(End Notes, 4) a group undergraduates at Appalaichan State University, gum arabic was introduced at different heights as to see what effect it had on the eruption height. Releasing the gum arabic at a lower height on the bottle had a positive effect on the reaction, as shown by a higher eruption height (1). This is due to the carbon dioxide bubbles in the bottle having more exposure time to the reaction (2). This was also reflected by another experiment where crushed Mentos were compared with unmodified ones (3). The crushed Mentos were less effective because they took longer to reach the bottom and the majority of the reaction happened while the Mentos particles were falling. Experimental Section (Procedure) Materials: -1 unmodified 1l bottle (control) -1 bottle with a hole drilled at 10 cm from the bottom (1 st mod) -1 bottle with a hole drilled 5 cm from the bottom (2nd mod) -1 modified syringe (5) -duct tape -wax paper -2 rubber bands -6 liters of Diet Coke -Ten rolls of Fruit Mentos Step 1: Insert Mentos into modified syringe, put wax paper Step 2: Pour soda into 1 liter bottle Step 3: push 4 Mentos into bottle Step 4: Measure height of the eruption Step 5: repeat steps 1 through 4 with the 2nd modified syringe, the one with the hole cut 5 cm from the bottom Results No valid data was collected as a result of faulty engineering. Conclusion In the experiment, it proved impossible to gather data as result of engineering flaws along with a few other mistakes. The seal between the syringe and the bottle failed to stay watertight, causing a loss of internal 43

pressure, and possibly caused a smaller eruption. A loss of carbonation also occurred when the Diet Coke was transferred from its original container to the testing bottle. A solution to these errors is to introduce the Mentos through a long tube placed through the top of the original bottle of Diet Coke, instead of pouring it into a modified one. Here is a materials list and procedure for this possible second experiment based upon this idea (There is also a diagram attached to the back): Materials: 1. PVC pipe, smaller in diameter than the neck of the bottle 2. Cut at lengths of 10 cm and 15 cm. 3. Copper wire 4. 3 2l bottle of Diet Coke 5. Duct tape (6) 6. Wax paper 7. Rubber bands Procedure: 1. For control, put Mentos in through the top, measure height 2. Put Mentos in 5 cm tube, seal at one end with rubber bands, wax paper 3. Put tube into top of the bottle, seal with duct tape 4. Push mentos through wax paper with copper wire 5. Record eruption height 6. Repeat with 10 cm tube End Notes Coffey, “Diet Coke and Mentos, What is really behind this physical reaction?” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” pg 555 Coffey, “Diet Coke and Mentos, What is really behind this Physical reation” Pg 556 Coffey’s paper was an investigation into the now popular Diet Coke and Mentos experiment. She and a group of undergraduates tested different aspects of the reaction, like changing the surface area using different ingredients, and introducing the Mentos in different ways. 5. The modified syringe we used had the top sawed off so the Mentos could be pushed in using the plunger. 6. An alternative to the duct tape, and probably a more effective mode of sealing the tube would be to use something like the screw top on the Geyser Tube. 1. 2. 3. 4.

Smaller Nozzle Size Creates Larger Spray during the Eruptions

Mentos

Evan H. and Michel I.

Summary: For our experiment, we covered a soda bottle with a geyser tube with three different covers to see the effects on the eruption caused by combining Mentos and diet coke. The covers that we used were a geyser tube with 1) a cap (1.5 cm opening), 2) a coke bottle cap with a hole (1 cm opening) and 3) a garden hose nozzle (0.5 cm opening). In so doing, we were able to see if a smaller nozzle size created a larger spray during a Mentos and diet coke eruption. The geyser tube with the coke bottle cap with a 1 cm hole created the highest eruption measurement of 396 and 401 cm. The geyser tube with the 1.5 cm hole in the cap created an eruption reaching 340 and 314 cm. The geyser tube with 0.5 cm hole garden hose nozzle created the lowest eruption height of 152 and 290 cm. Introduction: A liquid eruption can be created by increasing the pressure within a fluid held in a closed space. During a Mentos and Diet Coke experiment, Mentos mint tablets are introduced into a bottle of Diet Coke or Pepsi. The resulting reaction is a stream of soda, which is guided through the neck of the bottle. The reaction within the bottle is due to a rapid release of carbon dioxide bubbles. In its simplest form, the Mentos and diet coke experiment usually involves dropping Mentos mints into diet coke, resulting in a foamy eruption, which can often be several meters in height.Âš When the two elements combine, they result in a massive increase of carbon dioxide pressure released from the Diet Coke. It expands the liquid and forces it out the top of the bottle.Â˛ In the past there have been many theories to explain the science behind the Mentos Eruption. The first widely viewed Mentos eruption occurred on the David Letterman show on September 14, 1999 3. In terms of scientific research this field is still in its still a fairly unproven area. There have been numerous videos and TV shows documenting eruptions. One of the most well-known documented experiments is on the set of the TV program Mythbusteres 4.

Experiment: In this experiment, three nozzles of different size (0.5cm, 1 cm and 1.5 cm) were individually put onto a release mechanism called a geyser tube. The geyser tube was then loaded with a Mentos tablet, held in place by a pin, so that the Mentos tablet was held inside the geyser tube. The loaded geyser tube was then placed over a 1 liter bottle of Diet Coke. The pin was pulled, allowing the Mentos tablet to enter the bottle of Diet Coke. The emitted stream of liquid was measured for height. Each nozzle setup was sampled twice.

Graph 1

450 400 350

Height of 300 eruption 250 stream(cm) 200

Trial 1 Trial 2

150 100 50 0 Bottle cap w/ hole (1 cm)

Geyser Tube w/ cap (1.5 Nozzle cm) Type

Garden Hose Nozzle (0.5 cm)

Results:

Table 1

Nozzle

Height of stream (cm)

Bottle cap w/ hole Geyser Tube w/ cap Garden Hose Nozzle

Trial 1

Trial 2

396 340 152

401 314 290

Conclusion: During the Diet Coke and Mentos experiment, the different sized nozzles over the geyser tube proved to be the difference in average eruption height. As seen in the Graph 1 and Table 1, the smaller the nozzle width the higher the mentos eruption. This is up until the hole gets too small, at around 0.5 cm, as shown with the garden hose nozzle. These results most likely occurred due to the increase in eruption pressure from the soda. For example, if one was to spray an open hose, it generally does not go very far. But, when you use a thumb to close off part of the hose exit, the water accelerates and goes farther. Some errors that could have been present during the experiment were 1) a variable in the time it took to secure the geyser 46

tube on each coke bottle which allowed CO2 to release from the Diet Coke and 2) an imperfect nozzle fit, which allowed pressure to leak around the nozzle. Also, the nozzles could have been angled, changing the height of the eruption. One follow-up experiment could be to increase the number of width gradations (1, 0.85, 0.75, 0.65 and 0.5), in order to determine the point at which the nozzle width hinders the height of the eruption. The significance of these results shows that a smaller the nozzle width will cause a higher eruption when conducting a Diet Coke and Mentos eruption. Experiment Procedure: Gather materials: 10 one liter bottle of Diet Coke, 2 packages of mint Mentos, and a piece of ply wood (1 foot by 6 inches), one Mentos experiment plastic geyser tube with cap, measuring tape, water balloon hose nozzle, bottle cap with 1 cm opening Step 1: Extend the measuring tape vertically up the wall about 20 ft. Step 2: Put 2 Mentos mints in the geyser tube with the pin securely in place with the original cap of top of the tube. Step 3: Set up your experiment area by laying the piece of plywood down, next to a wall, near the measuring tape. Step 4: Place the closed bottle of diet coke on the ply wood, angled slightly at the wall. Step 5: Quickly unscrew the cap of the diet coke bottle, place the geyser tube in the top of the bottle and screw it onto the bottle. Step 6: Pull the cord attached to the pine, making sure it doesnâ&#x20AC;&#x2122;t tip the bottle, and run to a safe distance. Step 7: Record the eruption height on the wall, in comparison with the measuring tape Step 8: Repeat steps 2-7 once more. Step 9: Place the garden hose nozzle on top of the geyser tube and duct tape it on to ensure there is no pressure leakage Step 10: Repeat steps 2-8 with the garden hose nozzle Step 11: Place one of the coke bottle caps on a flat working environment Step 12: Hammer the nail into the center of the cap Step 13: Replace the top of the geyser tube with the bottle cap Step 14: Repeat steps 2-8 with the improved geyser tube End Notes: 1. Dr. H. Brielmann, The Guilford Journal of Chemistry. Volume 1, Page 1 (2007) 2. Tonya Shea Coffey, Diet coke and Mentos whatâ&#x20AC;&#x2122;s early behind the physical reaction. Page 551 (2008) 3. The original Letterman Show Mentos Eruption may be viewed on the internet 4.

(http://www.chem.uic.edu/marek/letterman0/video/mentos.htm.) The original mythbusters investigation of the mentos eruption may be found online at (http://dsc.discovery.com/videos/mythbusters-diet-coke-and-mentos.html).

High Surface Area increases a Coke Mentos Eruption Height Grace I and Amanda M

Summary: An increase in the surface area of a Mentos also increases the eruption height. According to the paper "Diet Coke and Mentos: What is really behind this physical reaction?" Tonya Coffey also agrees with this statement.1(551) When conducting the experiment, the data shows that when a Mentos was scratched on both of its sides the height of the coke and Mentos eruption increased compared to when the Mentos was left smooth or only scratched on one side. In fact, the Mentos eruption increased by 30% when the Mentos was scratched on both sides. However, our data did show that when the Mentos was scratched on only one side the eruption height was less, by one-third of an inch, then the eruption height of a smooth Mentos. This decrease may just be experimental error and if conducting the experiment again should be retested. Introduction: Coke and Mentos is a famous experiment where Mentos are dropped into a bottle of coke and the soda erupts. In our studies we tested to see how surface area effects the explosion. Other studies have been conducted and have also hypothesized that a rough surface of the Mentos can help break the strong polar attraction that water molecules have for each other by providing growth sites for the carbon dioxide.2(551) Our data conveyed the results that our hypothesis as well as the hypothesis in Tonya Coffey's paper are correct.3 (557) Increased surface roughness implies a higher surface area to volume ratio, meaning that more growth sites should be present on per unit volume.4 (556) In fact, surface roughness may be one of the most important causes of the eruption. 5 (556) Mentos with a lower surface area result in a smaller eruption. 6 (556) Tonya Coffey also tested different items other than Mentos to drop into the coke.7 (553) She found that Wint-O-Green Lifesavers, which had root-mean-square roughness of 2630, created the highest eruption compared to mint Mentos, fruit Mentos, and rock salt.8 (553) The Wint-o-Green Lifesavers have a rms roughness that is more than a factor of 10 larger than the rms roughness of the rock salt.9 (556) The Lifesaver reaction had the largest eruption spray.10 (556) Experimental: In this experiment, Mentos with different surface areas are dropped into 12 oz. bottles of coke. To do this experiment, you have to gather all materials: 9 bottles of coke, 9 Mentos, a geyser tube, a measuring tape, and a paper clip. Then, 3 of the Mentos have to be scratched with the paper clip, on one side and 3 of the Mentos have to be scratched on both sides. The remaining 3 Mentos will be left smooth on both sides. Put one of the smooth Mentos into the geyser tube and drop the Mento into coke bottle. Measure the height and record the data. Then do the same steps with the one side scratched Mentos, and the both side-scratched Mentos. Do 2 more trials for each surface area and record the data.

Mentos surface area Trial 1 Trial 2 Trial 3

Smooth

One side scratched 51 51 64

Trial 3 height 56 46 67

Average 41 49 48 48 79 70

Results: In this experiment, we tested how the surface area of the Mentos would react differently to coke. There wasnâ&#x20AC;&#x2122;t a significant difference between one side scratched eruption height and the smooth Mentos eruption height. The one side scratched Mentos average eruption height was 48 cm and the average eruption height was 49 cm. Although, there was a significant difference between the both sides scratched Mentos and the other two Mentos. The average eruption height of the both sides scratched Mentos was 70 cm or a 21 cm difference in height. The results were not always consistent. For example, the second trial for the smooth Mentos was 56 cm while the third trial was 41 cm. Some of the results were consistent, though. For example, the first trial height of the one side scratched was 51 cm, the second trial height was 46 cm and the third trial height was 48 cm, which were all relatively close in height. The two sides scratched Mentos were not that consistent either because the first trial eruption height was 64 cm or the second trial height was 79 cm. Conclusion: It was hypothesized that different amounts of surface area on Mentos would change the eruption height when the Mentos were dropped into coke. The hypothesis was proven correct, but only slightly. In the results section 49

it said that there was not a significant difference between the smooth Mentos, and the one side scratched Mentos eruption heights but there was a big jump in eruption height between those two and the both sides scratched Mentos. A scratched surface area on a Mentos makes the eruption height taller because the growth sites of the bubbles are already exposed. The reason for the smooth Mentos and the one side scratched Mentos having similar eruption heights was that the time it took for the coating to come off one the smooth Mentos was not that different from the amount of time the coating took to come off of the one side scratched Mentos. For the two sides scratched Mentos, though, the eruption was immediate because it barely had any coating on its surface which meant that there would be more carbon left in the coke to make a larger eruption. The surface area has to be completely scratched to make a significant difference in eruption height. It also stated in the results section that the data of the smooth and both sides scratched Mentos was inconsistent while the data for the one side scratched Mentos was consistent. It was predicted that the both sides scratched and the one-side scratched Mentos would have the inconsistent results because each Mento wouldnâ&#x20AC;&#x2122;t have been scratched the exact same amount. It was also predicted that the smooth Mentos would have very consistent data because they have the exact same amount of surface area. I believe that the results turned out the way they did due to errors in the experiment. One error was that some bottles of coke make have been shaken a little bit due to the process of taking the cap off, and putting the geyser tube on which leads to the other error. The other error that could have occurred was the amount of time in between taking the cap off of the bottle and dropping the Mentos into the coke bottle. The more time it took to get the mento into the bottle of coke, the more carbon was released from the bottle which meant that the reaction would be smaller. Changes I would make to this experiment if it were retested would be the amount of trials because some trials more have had error and that would affect the data. More trials would give a more precise and accurate reading of the eruption height of Mentos with different surface areas. In conclusion, high surface area of Mentos increases a Mentos eruption height. Endnotes: 1. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 2. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2007) 3. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 557 (2007) 4. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 5. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 6. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 7. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 8. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 553 (2007) 9. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007) 10. Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 556 (2007)

The Amount of Time between Opening a Bottle of Diet Coke and the Mentos Release Affects the Size of the Eruption Olivia S and Bronwyn R Summary This experiment tested the effect of the amount of time between opening a bottle of Diet Coke and the release of Mentos into the coke on the height of a Diet Coke-Menots eruption. It was hypothesized that if the amount of time between the opening of the Diet Coke and the Mentos release is increased, then the eruption will be smaller because there will be less carbon dioxide. To test this hypothesis, there where three different amounts of time used, thirty seconds, one minute and five minutes. There were two trials for each time tested. The average height of the eruption after thirty seconds was 60. 5 bricks (332.75 cm), after one minute was 52 bricks (286 cm), and after 5 minutes was 47 bricks (258.5 cm). Introduction This experiment came into the public eye after it was used on the David Letterman show in 1999 and after it was a subject on the show Mythbusters in 2006.x Since then, the experiment has become a popular science experiment in elementary to college level classrooms.x In its simplest form, the Diet Coke-Mentos explosion experiment is dropping fresh Mentos into a newly opened bottle of Diet Coke, creating an eruption that can range from a couple of inches to the world record of 29.2 feetx, depending on the number of Mentos placed in the soda.x The basic ingredients that cause this reaction are gum arabic and gelatin in the Mentos as well as the caffeine, potassium benzoate, and aspartame in the Diet Coke.x The carbonation in the soda also has an effect on the height of the eruption.x In this experiment, Diet Coke is used because it contains aspartame and caffeine, two crucial ingredients to the success of the explosion.x Mint Mentos were also used because they do not have an outer coating, like many other flavors of Mentos. This allows more CO2 bubbles to form on the candy, resulting in a bigger reaction.x

Materials Six bottles of Diet Coke Twelve mint Mentos One geyser tube One stopwatch A pair of safety goggles Tape measure (optional) Procedure 1. Place two Mentos inside the geyser tube 2. Put on safety goggles 3. Set coke bottle on the ground, next to a wall, and at an angle so that when an eruption occurs, the coke can hit the wall, making it easier to measure the height of the eruption. 4. Simultaneously open the coke bottle and start the stop watch 5. Screw the geyser tube onto the opening of the coke bottle- DO NOT release the Mentos 6. When the stopwatch reaches thirty seconds, release the Mentos and stand back from the coke bottle. 7. After the eruption has stopped measure up to the highest point of the eruption (which should be where the coke hit the wall) by counting the number of bricks it reached to, or using a tape measure. 8. Record the height of the eruption. Repeat this trial. 9. Repeat steps 1-8 replacing thirty seconds with one minute, then five minutes. 51

Results Our experiment tested the explosion height of the Diet Coke after different lengths of time from the opening of the bottle. On the whole, the longer the bottle had been kept open, the shorter the height of the explosion. For example, when the Mentos were dropped in 30 seconds after opening the bottle, the average eruption height was 60.5 bricks (332.75 cm), in comparison to the average of the 5 minute trial, where the average eruption was 47 bricks (258.5 cm). Time from Bottle Opening to Mentos Drop 30 seconds 60 seconds 300 seconds

Trial 1

Trial 2

Average

61 bricks (335.5cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60 bricks (330 cm) 52 bricks (286 cm) 47 bricks (258.5 cm)

60.5 bricks (332.75) 52 bricks (286 cm) 47 bricks (258.5 cm)

Time of Carbonation Release Vs. Eruption Height 400

350

Eruption Height (cm)

300

250 Trial 1 Trial 2 Average

200

150

100

0 30

300

Time (seconds)

Conclusion This experiment examined the effect of the amount of time between opening of the Diet Coke bottle and the Mentos release. The data collected strongly supports the theory that the more time elapses between the opening of the bottle and the release of the Mentos, the less explosive the reaction will be. This is most likely the case because the longer the bottle is opened prior to the reaction, the more time carbonation (which might be a catalyst in the reaction) has time to escape.x Because the carbonation is significantly decreased, the reaction yields a shorter spray height. A follow-up experiment might be to compare sodas with different expiration dates, as the ones with nearest expiration dates will have sat on shelves longer and most likely be flatter (less carbonated). Another follow-up experiment could be 52

to buy a set of sodas with the same expiration date and perform the experiment at different times in relation to the expiration date; for example, one could be set off one month prior to the expiration date, another on the date, and a third one month later. x

Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Dr. H Brielmann, Guilford Journal of Chemistry: Introduction to the First Issue of the Guilford Journal of Chemistry, Page 4 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Carly Clark and Jenn Agamie, The Guilford Journal of Chemistry Volume I: How the Coatings of Mentos Affects the Size of the Mentos Eruption, Page 17 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 551 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 554 (2008). x Professor Tonya Shea Coffey, Diet Coke and Mentos: What is really behind this physical reaction?, Page 552 (2008).

Fruit Mentos Caused the Largest Explosion as Opposed to Strawberry and Green Apple Mentos Ashely Z and Katie N

Summary Coffey’s results support that the fruit Mentos created a larger explosion because their coating dissolves more easily in water.1 she also states that the mint Mentos went just as high as the fruit ones, but we did not test the mint Mentos. Although Both Coffey’s and our data support that the fruit Mentos cause the highest eruption, the Mythbusters data conflicts. They added their own waxy coating which covered the rough patches that would have otherwise been exposed.2 According to professor Coffey, Aspartame that is found in diet drinks is more explosive3, which is why we used diet coke in our experiment. We also used Diet Coke because it has more aspartame than the preservative potassium benzoate, which prevents the eruption from going higher.4 we tied our Mentos together so they would sink to the bottom faster. Tonya Coffey’s study previously proved that the farther the bubbles have to travel through the liquid, the higher the explosion will go5. This may be why that in Coffey’s experiments the crushed Mentos did not go as far, which is why we chose to keep them whole. She also states that there is not always a direct relation in the distance traveled through the liquid, shown by her test with the molecular sieve beads6. The fact that we put holes through the center of our Mentos may have also contributed because more of the rough surface was exposed, which is one of the most important causes of the diet coke reaction.7 Coffey also found that the hotter beverages cause a higher eruption, so we didn’t refrigerate ours and kept them at room temperature.8 54

Introduction One of the most well-known experiments for science classes is the easy experiment of Mentos and Coke. In this experiment, the height of the eruption was tested to see if different types of Mentos were effective and if tying the Mentos together would help weigh them down to produce a bigger eruption with the different Mentos. Fruit Mentos and Diet Coke were used because in Tonya Coffeyâ&#x20AC;&#x2122;s article, she discovered that the fruit Mentos and Diet Coke were the most efficient in producing the highest eruption.9 the result of the experiment was that the fruit Mentos produced the highest eruption.

Experimental Section 1. Gather the required materials (Please see below). 2. Take 6 fruit Mentos and make a hole in the center of each of them using the specified nail. Then take the spool of thread and cut a thin piece of thread and string the 6 fruit Mentos together to make the Mentos fall to the bottom quickly. 3. Place 1 of the bottles of coke near the brick wall at a slight angle for measuring later and make sure that the bottle REMAINS CLOSED! 4. Very quickly, open the bottle, place geyser tube on top, and place Mentos in tube. Pull string out of the geyser tube to release Mentos and step away to prevent being sprayed. 5. Measure the height of the eruption based on the height of wetness of the wall. Either count the amount of bricks if using a brick wall and multiply that number by the length of the brick or use a long measuring tape and measure the height. Record data in cm. 6. Repeat once using fruit Mentos. Then repeat twice for each type of Mento using strawberry and green apple Mentos. Make sure that for each Mento type, there are 2 trials. Materials: 12 fruit Mentos, 12 green apple Mentos, 12 strawberry Mentos, a 2-inch 4-d (penny) nail, a spool of fine thread, pencil/pen, graph for recording data, 6 1L-bottles of diet coke, geyser tube, brick wall or hard surface to measure eruption height, measuring tape, and scissors to cut thread. Results The first trial that was performed was the first trial of the fruit Mentos. The eruption height of this was 198 cm which was the highest eruption and most spectacular recorded in this experiment. The second trial of fruit Mentos reached 181.5 cm. Next the green apple Mentos were tested and these produced very small wimpy eruptions compared to the fruit and strawberry Mentos. The first trial was 121 cm and the second trial was 154 cm. There may have been a minor error in the first trial due to the geyser tube (For more, please refer to the conclusion). The last set of trials was the strawberry Mentos. The strawberry Mentos landed in the middle of the results and yielded to relatively high eruptions. In the first trial, the eruption was 176 cm and the second trial height was 132 cm. In order of highest eruptions to smallest was fruit Mentos, strawberry Mentos, and then green apple Mentos. (For graph and table, please refer to end of paper.) Conclusion After completing this experiment, the results were that the fruit Mentos produced the highest eruption compared to the green apple Mentos and strawberry Mentos. The first trial may have had an error because the geyser tube was not all the way on and may have contributed to the lower height of eruption. The fruit Mentos may have had a rougher surface than the green apple Mentos, but another test would have to be done to confirm that hypothesis. The hypothesis stated before would make an excellent follow-up experiment to determine if that is the reason why the fruit Mentos went higher than the green apple and strawberry Mentos. Another follow-up experiment could be to try tying the Mentos in different ways to force them to the bottom quickly to determine if that has any effect on the eruption height of the Mentos.

Endnotes 1. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 2. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554-555. 3. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 4. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 554. 5. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 6. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 555. 7. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 8. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 556. 9. Coffey, Tonya. “Diet Coke and Mentos: What is really behind this physical reaction?” June 7, 2007: 552.

Trial 1

Trial 2

Fruit Mento

198 cm

181.5 cm

Green Apple Mento

121 cm

154 cm

Strawberry

176 cm

132 cm

Height of Eruption (in cm)

Height of Eruption with Different Types of Mentos 250 200

Tria l1

150

Tria l2

100 50 0 Fruit Mento

Green Apple Mento Type of Mento

Strawberry

Period Seven

The weakening effects of Baking Soda and Sugar on the height of a Mentos in diet coke eruption The first time our group performed the experiment we tested how high five Mentos candies would erupt within a bottle of diet coke. We found that the average height at which it erupted was 131.5 cm. We came to this height by counting how many bricks the eruption went up, and measured the length of each brick in centimeters. Upon adding the baking soda and sugar to the diet coke, the eruption was much less impressive, since it hardly erupted higher than the top of the bottle, at about 11 centimeters for sugar and 8 centimeters for baking soda. The reason that it did not go that high was because by the time we got the Mentos into the coke, it had already begun to react. We can determine that the baking soda and sugar were both weakening factors to the eruption of the diet coke. Vinegar didnâ&#x20AC;&#x2122;t seem to alter the reaction as much, but it did make it go lower. The height of the eruption with vinegar was 76 centimeters. Introduction For our experiment we decided to verify Tonya Coffeyâ&#x20AC;&#x2122;s results and test the effectiveness of adding baking soda to the diet coke. According to Coffeyâ&#x20AC;&#x2122;s results, when she added baking soda to the soda it erupted to a height of 15.5 feet, or 472 centimeters.x We also wanted to see how sugar added to the soda would affect the eruption. We came to the conclusion that diet coke does not react as well with sugar or baking soda, because our resulting heights for those experiments were much lower than the control. When adding baking soda and sugar to the diet coke at the same time, we saw that each time, the bottle would overflow without adding any Mentos to it. Experiment Gather all Materials needed for the experiment Using a tube that can release objects with the pull of a string, and place five mentos within the tube. Open the diet coke, and as soon as possible place the tube over the coke and drop the mentos in, taking care to tilt the nozzle towards the wall so that the soda leaves a mark that can be measured Measure how high the soda shot upwards, and record the results; this will be your control Add 20 ml of vinegar to the soda and then put the nozzle on and repeat the process Add 20 ml of sugar to the soda and then put the nozzle on and repeat the process Add 20 ml of baking soda to the soda and then put the nozzle on and repeat the process Compile the data and graph it

Results We found through our experiments that baking soda and vinegar lessened the effects of the diet coke and Mentos eruption. Initially when we tested the diet coke it went up 48 bricks, which is equal to 131.5 centimeters. That was the average of three tests we performed. We came to the conclusion that adding sugar would decrease the reaction because when we added it, the soda overflowed before the Mentos even entered the soda, which made it go up only 11 centimeters. The addition of baking soda was equally as unsuccessful in increasing the reaction, because it reacted with the soda before the Mentos went in and only caused it to erupt 8 centimeters. However when we added vinegar we did get a successful reaction, for the average of the three trials was 27.5 bricks which is 76 centimeters. Graph

Effect of sugar, vinigar, and baking soda on the height of a mentos eruption 140 120

Height (cm)

100 80 Series1 60 40 20 0 Control

20 ml sugar

20 ml vinigar

20 ml baking soda

Things we added Conclusion

Since the results we found for these additions were harmful to the eruption, we can pretty safely determine that they do not make the coke more open to erupting. We did not think this would be the case, because according to Coffey, baking soda at least should have increased the reaction.x According to NASA even, adding a sugary substance to diet coke should create a reaction with the coke, which shows why we did get a small reaction after adding the sugar.x A possible reason we did not get strong results for when we just added the baking soda, vinegar, and sugar to the bottle is that there was too wide of a nozzle for the soda to escape from, which made it not go as high.x Also the reaction might have started as soon as the sugar was put into the coke, which would have made the mentos less effective.x An additional reason the baking soda might have caused the reaction to slow down, is because baking soda is a base which would take away the acidity of coke.x Also the amounts of coke and variables used were different then the ones done in other experiments, which must have some impact on the results of the experiment.x In the future, other people could place the soda bottle more carefully, or the pull the strings of the gyser more carfully so it doesn’t tip overx, make sure that the bottle wasn’t shaken around before performing the experiment,x and make sure that you’re using all the same flavor Mento’s for the same trial.x x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011.

Voltz, Stephen M. "Nozzle for Creating Geyser-like Fountains." USPTO Assignment Database. Frederick Globe, 21 Sept. 2007. Web. 10 Oct. 2011. x

Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Coffey, Tonya Shea. "Diet Coke and Mentos: What Is Really behind This Physical Reaction?" American Journal of Physics 76.6 (2008): 551. Print.

Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x Rust, Cashman R. "NASA ADS: Explosive Volcanism Lessons Learned from Mentos and Soda Eruptions." NASA Astrophysics Data Center. American Geophysical Union, 14 Nov. 2006. Web. 10 Oct. 2011. x Voltz, Stephen M. Effects of an Acidic Beverage on Dental Maintance 08th ser. 36.8 (1996): 1775-781. Antimicrobial Agents and Chemotheropy. American Society for Microbiology, 21 Oct. 1998. Web. 10 Oct. 2011. x

The Mixture of Mint and Fruit Mentos Produced the Largest Eruption Jack F and Jamie W

Summary The experiment being tested was if two mentos were dropped into a diet coke bottle, which one would have the highest eruption? The types of mentos that were used were fruit, apple, and mint; and the trials were two mint, two fruit, two apple, one mint one fruit, one mint one apple, and one fruit one apple. Two mint is considered the control due to it being the most common mento. If two mentos are placed into a diet coke bottle, then two fruit mentos will have the highest eruption because fruit mentos have a smoother shell, creating more pressure build up. Once the experiment was performed, one apple and one mint mento combination had the largest eruption, which was 46 bricks high. The next two highest eruptions were two mint mentos at 43 bricks, and one mint one fruit at 40 bricks high. Two apple mentos had the smallest eruption, which only went 27 bricks high. A combination that contained one mint went 100% as high as the control, where as a combination containing apple went 95.3% as high, and fruit went 88.3% as high as the control. Introduction The amount of mentos added to a bottle of diet coke will affect the size of the eruption. With each mento added to a bottle of diet coke, the height of the eruption spray rises proportionally.x Also, different mentos react differently with the diet coke. Fruit mentos are known to react and cause a larger spray than a mint mento would. This is because fruit mentos have a smoother surface, with fewer rough patches, which dissolves faster in the soda.ii Due to the short amount of time it takes for these to dissolve, carbon dioxide bubbles build up inside the bottle. The more buildup of the co2, the more pressure inside the bottle, which forces the soda out of the nozzle faster. x Experimental Section

There were three different flavors of Mentos used, mint, fruit and apple; and a total of six different combinations, or trials. The trials were two mint, two apple, two fruit, one mint one fruit, one mint one apple, and one fruit one apple. These different combinations were placed into the nozzle compartment, and when released, dropped into the soda creating an eruption. The height of the eruption was measured in bricks. Procedure Obtain two mint Mentos, a nozzle compartment with pin, and a diet coke bottle Screw the nozzle compartment onto the diet coke bottle, and put the lock pin in place Place the two mint Mentos into the nozzle, secured by the pin Remove the pin, watch eruption and count the height in bricks Record data Repeat for each trial Supplies One pack of mint Mentos One pack of fruit Mentos One pack of apple Mentos One 6-pack of diet coke, 20oz per bottle A nozzle compartment with a loader pin Safety Precautions Always wear safety goggles Stand safe distance away Do not create too much pressure in the bottle, where it will explode Results 46

1 Mint 1 Apple 40

1 Fruit 1 Mint

1 Fruit 1 Apple

Height of Eruption (in bricks)

2 Apple

2 Fruit

2 Mint 0

Mento Eruptions Results The combination of 1 mint and 1 apple mentos had the highest eruption. This eruption went 46 bricks high, 3 bricks higher than the height of the second eruption. The second highest eruption was 2 mint mentos, which went 43 bricks high. Next, 1 fruit and 1 mint mento had an eruption height of 40 bricks. From this point there was a drop off it eruption height. 1 fruit 1 apple mentos went 36 bricks, and 2 fruit mentos went 33 bricks high. Lastly, 2 apple mentos 60

erupted to only go 27 bricks high. The reaction between the 2 apple mentos was the only number that stood out as somewhat of an outlier. Conclusion After the conduction of the experiment to search for the perfect combination of Mentos flavors that would have the loftiest of height compared to the other combinations, Fitzgerald and Webb concluded that the grouping of the mint and apple flavored Mentos erupted the to a measure of forty-six bricks high. This result was followed by the combination of two mint Mentos (forty-three bricks high), mint and fruit Mentos (forty bricks high), fruit and apple Mentos (thirty-six bricks high), two fruit Mentos (thirty-three bricks high), and two apple Mentos (Twenty-seven bricks high). The reason for why the recipe of the mint and apple Mentos erupted the highest was partially because two mint Mentos in an explosion were second to the mint and apple candies in elevation. Besides the mint candy being the necessity for a perfect combination of Mentos for a large eruption, the ingredients in the mint and apple candies may have a simultaneous reaction with either each other or with the Coke itself.i Although the two apple candies went the lowest in altitude compared to the other dependant variables, it still combined for an extreme reaction with mint.ii Lastly, for further study, one might somewhat reenact this experiment by attempting to combine three, four or even more Mentos in order to find the arrangement for the perfect Coke and Mentos eruption. In conclusion, Fitzgerald and Webb discovered that the formula of apple and mint Mentos in a Coke and Mentos experiment were the ideal combination to achieve the highest rise of coke from the ground.

Manipulating the Surface of Mentos: The Resulting Diet Coke and Mentos Explosion Height will Increase if the Increased Surface Roughness is Greater Than the Losses of Mass and Gum Arabic Juandiego C Summary: In this specific experiment, the surface texture was tested. However, it was discovered that it is extremely difficult to physically manipulate the surface texture of the Mentos without a resulting loss of mass and gum arabic. Therefore, three different groups with different surface roughness increase to mass/gum arabic loss ratios were tested to explore the resulting effects; one group of Mentos was grazed lightly with sandpaper, one had holes poked into it, and one had the coating completely scratched off- were tested. In comparison to the eruption height of a normal Mentos candy, the group with holes went 7% higher, the sandpapered one went 13% higher, and the one with no coating went 25% lower. Introduction: The diet coke and Mentos reaction is a fun experiment for physics and chemistry classes ranging in all different grade levels. The diet coke and Mentos candy eruption occurs when new Mentos are dropped into a freshly opened bottle of diet coke. The eruption can be multiple meters high (the record is 29.2 ft).1 This reaction was first shown on the Dave Letterman Show in 1999 and was the subject of a 2006 Mythbusters episode.2,3 There are few verified discoveries regarding the Mentos and diet coke eruption. Many experiments have inferred that additives, “viscous drag”, and temperature have a large impact on the explosion height. 4 However, it has been cited that surface roughness is a crucial factor of the reaction.5 When the Mentos candy falls to the bottom of the bottle, carbon dioxide bubbles form on it; then they detach and rise to the top. The bubbles act as nucleation sites for carbon dioxide still dissolved in the liquid. This discharges more carbon dioxide and creates a larger explosion.6 The higher surface area results in more growth sites present per unit volume. This theory is proven with Coffey’s experiment. Two of the combinations tested were Wint-o-Green Lifesavers and diet coke and rock salt and diet coke. The Wint-o-Green lifesavers had a rms roughness of 10 more than the rms roughness of rock salt. The Wint-o-Green’s higher surface area is one of the main factors that resulted in its explosion having more distance and losing more mass than the salt and diet coke. 7 In addition, an experiment done by Hill and Gaboury, two students of Guilford High School, showed that drilling holes into Mentos resulted in the eruption going higher than regular mentos.8 The intensity of the Diet Coke and Mentos eruption is moreover due to the presence of gum arabic in the Mentos candy coating.9 Gum arabic is a surfactant that increases the intensity of an explosion by reducing the surface tension of water.10 In Coffey’s paper, the presence of liquid gum arabic in Diet Coke soda caused a reaction without surface roughness.11 However, despite gum arabic’s important contribution to the explosive reaction between Diet Coke and Mentos, it is extremely hard to physically manipulate the surface area of Mentos candies without the losing amounts of it. The purpose of this lab is to further test the relation between these two properties behind the explosion. Experiment: In this experiment, we altered the surface of Mentos three different ways and then measured the height of the reaction between each Mentos and diet coke. We separated the green apple Mentos into four different groups to test our independent variable. With the first group we abraded the surface of the Mentos with sandpaper to create grooves in the surface. The second group we used sandpaper again to remove the candy coating of the Mentos completely, and the third group we used the metal tip of a mechanical pencil to make approximately ten holes in the front and back of the Mentos. The final group we kept the same to serve as a control group to compare the rest of our data to. The constants held in the experiment were the type of mentos, the size of the hole poked in the Mentos, the brand of soda, the bottle size, the extent of grazing on the first group of Mentos, and the number of Mentos used in each trial. After we prepared the Mentos we set up a 355 mL bottle of diet coke against a brick wall. We placed a flat whiteboard beneath the can to keep it from falling over and put soda lids in about a two inch stack under the side of the whiteboard away from the wall. This allowed the soda to splash onto the wall leaving a mark that would make measuring easier. 62

We placed two regular Mentos into a geyser and screwed the geyser on top of the open bottle just prior to the experiment to minimize the loss of carbon dioxide gas. 10 Then, we put on safety goggles, pulled the pin out, and stepped back a safe distance from the eruption. We recorded the number of bricks high the soda reached, and then repeated the step for multiple trials. We did the same procedure for the other three groups of Mentos. Results: The recorded heights for each type of Mentos can be observed in Table 1 and can be compared in Graph 1 or Graph 2. We conducted between three to six trails per type of Mentos. The average height for regular Mentos was 176.0 cm, 198.9 cm for sandpapered Mentos, 188.8 cm for Mentos with holes, and 132.0 cm for Mentos without the candy coating. We chose to use four significant numbers instead of the two that is required for the multiplication and division rules to increase the accuracy of our figures. The percent error for sandpaper is 0.008%, and the percent error for Mentos with holes is 0.03%. The other two groups divided equally as the average. The Mentos with holes in them had a resultant height 7% higher than the control group. The height of the sandpapered Mentos yielded an eruption height of approximately 13% higher than the control group on average, and the Mentos without coating had an eruption height about 25% lower than that of the control group.

The Effect of Drop Height on the Height of the Mentos Eruption Summary: For our experiment, we dropped two mentos using 1 geyser tube, 2 geyser tubes, and then 3 geyser tubes to see if the height at which the mentos were released played a role in producing higher eruptions. Throughout the experiment we used the 473 milliliters of Diet Coke for every trial. The average height when using one geyser tube was 136 cm, two geyser tubes increased the height by 3.5 bricks making its average height of 158 cm, and three geyser tubes further increased the height with an average of 196 cm. The results also showed that there was a 16% increase when using 2 geyser tubes instead of 1, a 24% increase from 2 geyser tubes to 3, and a 44% increase from 1 geyser tube to 3 geyser tubes. At the end of the experiment, the results demonstrate that the higher the mentos are released the higher the eruption. Introduction: When the Mythbusters team tested the mentos eruption they found that the speed with which the sample falls through the liquid is a major factor in contributing to higher explosions. If the bubbles [produced during drop] must travel farther through the liquid, the reaction will be more explosive. Longer distances traveled by the bubbles result in more explosive reactions. In contrast, the mentos released from 1 geyser tube produce particles moving through the fluid at a slow speed, since they do not gain as much velocity, and do not travel as far down into the bottle. The Mythbusters further concluded that samples, which encounter less viscous drag and hence fall more quickly through the soda, will cause more explosive reactions. Experimental Section: This experiment is being used to see if the height of the drop of mentos has a noticeable effect on the height of a menots eruption. During this experiment, there will be three lengths of geyser tubes. 1 geyser tube, 2 geyser tubes taped together, and 3 geyser tubes taped together. These should be duck taped together very well to ensure that no cracks let eruption foam out of the sides. Results: The Effect of Drop Height on the Height of the Mentos Eruption Height of Eruptions (cm) Number of geyser tubesTrial 1 Trial 2 Trial 3 Trial 4 Average 1 152 152 127 114 136 2 158 158 152 165 158 3 190 215 177 203 196 Our data shows that the higher the mentos were dropped, the higher eruption it produced. For example, the average for the 1 geyser tube drop was 136 cm, the average for the 2-geyser tubes drop was 158 cm, and the average for the 3geyser tubes drop was 196 cm. This shows that as the height of the drop increased the eruption height of the mentos increases as well. There is no suspect data in this experiment because all of the numbers are close together for each height drop range. Experimental Procedure: These are the steps to follow in order to perform this experiment. It is important to have safety goggles on during the entire experiment. 1. Place 2 fruit Mentos in 1 geyser tube connected to the 16 oz. bottle of diet coke making sure they do not fall directly through. 2. Place the soda on a flat surface and then release the Mentos and record the height of the eruption. 3. Repeat steps 1 and 2 three more times 4. Gather 2 geyser tubes and connect the two with duct tape and then place the Mentos in the top tube making sure they stay in place. 5. Release the Mentos into the soda from a flat surface and record the height of the eruption. 6. Repeat steps 4 and 5 three more times 7. Now with 3 geyser tubes, connect all three of them with duct tape and drop the 2 fruit Mentos into the top tube. 8. Release the Mentos into the soda with a flat surface underneath and record the height of the eruption. 9. Repeat steps 7 and 8 three more times 64

Conclusion: At the end of the experiment, from the results that were collected, we discovered that the higher Mentos are dropped, the higher their eruption will be. The results from the experiment supported the Mythbusters theory from the work of Coffey because dropping the Mentos using 3 geysers tubes versus 1 geyser tube shows a significant difference in eruption height because the Mentos dropped from the top of 3 geyser tubes have more velocity; therefore, they fall farther down in the soda bottle. This is shown several times throughout the data because as it can be seen in the graph and table above, the height of the eruption is always higher for the higher drop distances. For example, in trial 2 for all of the heights, the 3-geyser tube drop is significantly higher than the other 2 drops with 1 and 2 geyser tubes In addition, in many of the trials, the data is never any close than 6 cm in height difference, which is a sizeable margin. If higher drop heights were tested, the data would most likely be linear because the height of the Mentos eruption would increase at a steady rate as the drop height increased and our data supports this concept. Perhaps at a certain drop height it could break the world record. The reason for these results could be that as the Mentos drop they gain more velocity, therefore creating a larger explosion. In the future, there could be multiple follow-up experiments to further solidify the position that the higher Mentos are dropped into diet coke, the larger eruption will occur. For example, there could be an extended experiment on this one that was performed, where the height is dramatically increased, and it tests how extreme the results can become.

Mentos, Baking Soda, and Vinegar….A Quench to an Eruption’s Thirst. Rebecca E and Klaire C Summary The experiment completed consisted of using additives (baking soda and vinegar) to a soda and mentos eruption. The control of the experiment (1 mento and 1 bottle of soda) reached a height of 35 bricks. The first trial which consisted of ½ teaspoon of baking soda and 1 teaspoon of vinegar reached a height of 13 bricks. The second trial which had ½ teaspoon of baking soda and 2 teaspoons of vinegar reached 32 bricks. The third trial had ½ teaspoon of baking soda and 3 teaspoons of vinegar reached 13 bricks. And finally the fourth trial which had ½ teaspoon of baking soda and 4 teaspoons of vinegar reached a height of 0 bricks. Overall it was found that the more vinegar that was added to the mixture, the lower the eruption height was. Introduction The Mentos eruption is an experiment that can be changed in multiple ways. It has been seen on Mythbusters (3) and the David Letterman Show (4). Kids and adults of all ages have tried their own version of the “Diet Coke and Mentos” (10). Our experiment involved using additives (baking soda and vinegar) to see if it would increase the height of the eruption. We used baking soda at a constant of 2.5 grams and increased the amount of vinegar for each of the 5 trials. Robins and Turcio (2) had the same idea in which they referred to it is as a “volcanic eruption”. Diet Pepsi was found by Musterer and Ruotolo (1) to have a higher eruption than diet Coke. They determined that the additives almost entirely quenched the eruption. Cutler and Smith discovered that frozen mentos dramatically increase the eruption (7). The other resource we had, the article by Tonya Coffey, did not have any information about our specific experiment but it did have useful conclusions such as the higher temperature of the soda causes a greater eruption (6). The speed at which the mento is dropped is also a major factor in the eruption along with the idea that gum arabic and gelatin in mentos and potassium benzoate and aspartame in caffeine cause explosion (5, 9). In the experiment, there was a period of 15 seconds before the mento was dropped into the diet coke solution, therefore, adding water, sodium acetate, and carbon dioxide to the eruption. There was no information on these substances in our sources, but we can conclude that they altered the eruption because it added more to it. This made our experiment more complex than we had intended because there were five additives instead of the two that were intended. The additive creates the reaction NaHCO3 + CH3CO2H – CH3CO2Na + H2O + CO2. This reaction and the baking soda and vinegar solution quenched the overall eruption.

Experimental section Trial number Amount of baking soda Amount of Vinegar CONTROL 0 grams 0 teaspoons 35 bricks 1 (.5 teaspoon) 2.5g (1 teaspoons) = 4.9289 mL 13 bricks 2 (.5 teaspoon) 2.5g (2 teaspoons) = 9.8578 mL 32 bricks 3 (.5 teaspoon) 2.5g (3 teaspoons) = 14.7867 mL 13 bricks 4 (.5 teaspoon) 2.5g (4 teaspoons) = 19.7156 mL 0 bricks

Height of eruption

The experiment done here was based on using additives. The first step was to obtain (6) 8 oz bottles of diet coke, baking soda, white vinegar, a teaspoon, mint mentos, and a geyser tube. The first step in the process of the eruption was to run a control. This means nothing is added to the soda but a mento and a geyser tube, the string is pulled, and the height of eruption is recorded. Then the next step is to run the first trial of the experiment. The first step 66

is to cover the teaspoon in a coating of baking soda so that the spoon is half filled with baking soda. Then the vinegar is poured into the spoon and added into the soda. A minor eruption occurs here so waiting 15 seconds after the eruption helped to keep the experiment more accurate. Then a geyser tube is inserted into the soda with a mento into the soda and the height of eruption is recorded. For each trial, the amount of baking soda is constant but the amount of vinegar is increased. Now all steps can be repeated for each trial. Results *note: trial 1 is an outlier so that data will not be included in graphs. *note: all conversions were done online on Google calculator. ***note: observation: the more vinegar that is added the lower the final eruption will be

Conclusion With the provided data, it is suggested that if a constant amount of baking soda and increased amount of vinegar is added to a Mentos eruption, the more vinegar there is, the lower the eruption will be. The control in the experiment with no baking soda or vinegar went a height of 35 bricks. But as soon as more baking soda and vinegar was added, the eruption significantly lowered each trial, going from a height of 35 bricks, to 32, to 13, to no bricks. The amount of baking soda remained constant in every trial, but the amount of vinegar in each trial was increased. When at its maximum amount, the amount of vinegar was 4 teaspoons and there was no eruption, even with baking soda added to the mixture as well. This compares to the control of 35 bricks with no additives in the solution, making a difference of 35 bricks. Another comparison that can be made is to the third trial. The total eruption height was 32 bricks, as opposed to the end result of 0 bricks. It is very clear that the amount of vinegar in a Mentos eruption has a significant effect on eruption height, obviously lowering the overall eruption height. Now the question of why did this happen comes up. A potential reason as to why vinegar quenches the eruption could be because of an imbalance of baking soda and vinegar. In a typical baking soda and vinegar reaction, there is always a huge explosion but when the amounts of both additives are altered it could affect the explosion. Another thought as to why the vinegar could have affected the explosion is because the baking soda mainly caused a minor eruption in the soda by itself when it was first added to the mixture, so by adding the vinegar it could have caused a reverse reaction where it did the opposite of what it normally does in a typical reaction because soda is in the mix. Finally, if the experiment was done over again more trials would be added for more data points, more accurate measurements would be taken, more precise procedures would also be taken to prevent invalidity of data, and more additives and background research would have been done to get a more clear understanding of the experiment before it was started. Citations 7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007). 1.Angelise Musterer and Lindsay Ruotolo, Guilford Journal of Chemistry, Volume 2, Pages 12-14 (2008). 2. Kelsey Robins and Laura Turcio, Guilford Journal of Chemistry, Volume 2, Page 38 (2008) 3. Mythbusters. Videocassette. Discovery Channel, 2006. 4. The Late Show with David Letterman. Videocassette. CBS, 1999. 5,6,8,9,10: Tonya Coffey, Diet Coke and Mentos: What is Really Behind This Physical Reaction?

Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Rebecca E and Klaire C

Coke Zero, Diet Pepsi, Sprite, Club Soda: Summary: For this Mentos Eruption, the sodas used were Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda, the goal was to see which soda produced the highest eruption. This variation of soda helped the observer see how different variables directly affect the height of the sodas eruption. This experiment the researchers found that Diet Coke caused the highest eruption out of all the sodas tested with an average of six bricks or thirty-three centimeters. Mountain Dew, Sprite, and Club Soda all fell short with an average of two bricks or eleven centimeters. Coke Zero came in second with an average of five or twenty-seven and a half centimeters. Diet Pepsi came in third with an average of four bricks, or twenty-two centimeters. This directly contradicts the work of Angelise M & Lindsay R. Through all this data a mathematical formula can be created where X is equal to the soda and Y equals the height and Y=X. Introduction: In earlier tests done by other researchers to find the soda that provides the best soda eruption, Diet Coke had been used. In this experiment the data shows that is because it does, in fact provide the best Mentos eruption. In an experiment done by Tonya Shea Coffey1, Coffey’s data supports the facts of “Which soda provides the best Mentos eruption; Diet Coke,” where Diet Coke provides the best Mentos eruption. Yet, when this data was compared with “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks” By Angelise & Lindsay R, it was found that the data was not supported and Diet Pepsi had the highest eruption. In the “Introduction to the second issue of the Guilford Journal of Chemistry, M and R’s3 data on Diet Pepsi is said to be 100% higher relative to Diet Coke. In another study, “The Effect of Soda Type on the Height of Mentos Eruptions,” by Ethan S and Zack B, data supported the data of “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” with Diet Coke being Shore and Browns’5 highest soda eruption too. The experiment “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” used strawberry, fruit, Mentos, which Coffey1 found to help make the largest eruption. In an experiment completed by Allison F and Jess L, they found that mint Mentos and Fruit Mentos have the same size eruptions. In an experiment in the American Journal of Physics, Fruit and Mint Mentos were found to have the same size eruptions also. Unlike K and R from the “Introduction to the Second Issue of the Guilford Journal of Chemisty,” the experiment, “Which Soda Provides the Best Mentos Eruption; Diet Coke, Sierra Mist, Mountain Dew, Coke Zero, Diet Pepsi, Sprite, Club Soda: Diet Coke!” did not cut the Mentos in half before adding them into the soda, they kept them whole. Experimental Section: The experiment that was done, by Rebecca E and Klaire C, was accomplished by having three trials, per soda, completed. With-in each trail a single Mento was dropped into a freshly opened bottle of twelve-milliliter bottle of soda. Results: Trial 1 Trial 2 Trial 3 Diet Coke 33 cm 33 cm 33 cm Sierra Mist 16.5 cm 11cm 11 cm Mountain Dew 5.5 cm 11 cm 16.5 cm Coke Zero 33 cm 27.5cm 22 cm Diet Pepsi 16.5 cm 22 cm 27.5 cm Sprite 11 cm 11 cm 11 cm Club Soda 22 cm 0 cm 11 cm (Each Brick is equal to 5.5 cm)

Conclusion: For our experiments, we found that out of the seven sodas we used, Diet Coke worked the best. For all three of the trials, Diet Coke’s foam shot up an average of 6 bricks, 33cm. The soda that had the next largest foam height was Coke Zero with an average of 5 bricks, 27.5cm and the third largest foam height was Diet Pepsi with 4 bricks, 22cm. According to Ethan S and Zack B, Diet Coke had the second largest explosion with an average of .85m and Sprite had the 3rd largest explosion, with an average of .51m1. Our results are not completely accurate because the first day of experimenting we did not have a string so we had to substitute a stick for it. The stick could have had a negative effect because it was thicker than the one attached to the string that we used the second day. Also, when we pulled both the sting and the stick sometimes the soda would fall over causing the data to be not as accurate as it could have been. “Sometimes, my hand partially hit an explosion, perhaps causing the height to drop” 2, like the picture shows on the right. The same thing happened in our experiment as well. A follow up experiment would be to try the different sodas with a different type of Mentos to see if the different flavors have an effect with the sodas. Something else we could do, would be to try less types of soda and do more trials to get our data more accurate. Experimental Procedure: 1. Get 12 ounce bottles of Sprite, Coke Zero, Diet Coke, Diet Pepsi, Club Soda, Mountain Dew and Sierra Mist as well as Mentos. 2. Open bottle and attach the geyser tube. Attach the string and drop the Mento in. 3. Pull the string and measure how high the foam goes. Record it in a data table. 4. Repeat steps 2-3 for each bottle. Endnotes: 1.“Diet Coke and Mentos: What is really behind this physical reaction?”, Tonya Shay Coffey. Received 7 June 2007; accepted 5 February 2008. Pages: 551, 552, 553, 556. 2. “Guilford Journal of Chemistry” (First- Second Issues) Editor and Chief: Dr. H. Breilmann. Pages: 1,2,3,4 3. “Diet Pepsi –Not Diet Coke – Produces Highest Results in Mentos Eruption When Compared to Other Diet Carbonated Drinks”, By Angelise M & Lindsay R http://chemistryadventure.com/Documents/b2.%20Diet%20Pepsi,%20not%20diet%20coke%20is%20the%20highest.pdf 4. “Cinnamon Mentos Erupt 20% Higher than Mint Mentos”, By Allison F and Jess Lhttp://chemistryadventure.com/Documents/b1.%20Cinnamon%20Mentos%20Erupt%2020%20percent%20higher.pdf 5. “The Effect of Soda Type on the Height of Mentos Eruptions”, By Ethan Sand Zack B. http://chemistryadventure.com/Documents/b9.%20The%20Effect%20of%20Soda%20Type%20on%20the%20Height%20 of%20Mentos%20Eruptions.pdf